A search plane covers 50 square miles of countryside. How many hectares does the plane search?

1,295
12.95
129.5
12,950

The probability that 3 of the next 10 households that a student visits will purchase a raffle ticket is 25%

From the question, we have the following parameters that can be used in our computation:

The probability is calculated as

P(x) = nCx * p^x * (1 - p)^(n -x)

Where

n = 10

p = 25%

x = 3

Substitute the known values in the above equation, so, we have the following representation

P(3) = 10C3 * (25%)^3 * (1 - 25%)^(10 -3)

Evaluate

P(3) = 0.25

Hence, the probability value is 25%

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The state lottery commission should have $513,446.50 in the bank initially to guarantee the payments.

To determine how much money the state lottery commission should have in the bank initially to guarantee the payments, we will calculate the present value of the annuity.

Given:
- 20 installments of $50,000 per year
- First payment made immediately
- n = 19 payments at the end of each year
- Interest rate = 4% per year compounded yearly

Step 1: Calculate the present value of the annuity.
PV = PMT * [(1 - (1 + r)^(-n)) / r]
where:
PV = present value of the annuity
PMT = periodic payment amount ($50,000)
r = interest rate per period (4% per year or 0.04 as a decimal)
n = number of periods (19 years)

Step 2: Plug in the given values and solve for PV.
PV = $50,000 * [(1 - (1 + 0.04)^(-19)) / 0.04]
PV ≈ $50,000 * [1 - (1.04)^(-19)] / 0.04
PV ≈ $50,000 * [1 - 0.629243] / 0.04
PV ≈ $50,000 * [0.370757] / 0.04
PV ≈ $50,000 * 9.26893
PV ≈ $463,446.50

Step 3: Add the first payment to the present value.
Since the first payment is made immediately, the commission should have the present value of the remaining 19 payments plus the first payment of $50,000 in the bank initially.

Initial amount = PV + first payment
Initial amount = $463,446.50 + $50,000
Initial amount = $513,446.50

The state lottery commission should have $513,446.50 in the bank initially to guarantee the payments.

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There are 151200 distinguishable permutations for the word CONFERENCE

From the question, we have the following parameters that can be used in our computation:

CONFERENCE

In the above word, we have

Letters = 10

Repeated C = 2

Repeated N = 2

Repeated E = 3

Using the above as a guide, we have the following:

The number of distinguishable permutations for the word is

Number = Letters!/Repeated letters!

This means that

Number = 10!/(2! * 2! * 3!)

Evaluate

Number = 151200

Hence, there are 151200 distinguishable permutations

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The cost of 2 rubber stamps is $2.06.

Let x be the cost of 2 rubber stamps.

We can set up a proportion to solve for x:

10 rubber stamps / $10.30 = 2 rubber stamps / x

Simplifying this proportion:

10 / 10.30 = 2 / x

Cross-multiplying:

10x = 2 × 10.30

10x = 20.60

Dividing both sides by 10:

x = 2.06

Therefore, the cost of 2 rubber stamps is $2.06.

The equation that would help determine the cost of 2 rubber stamps is:

10 rubber stamps / $10.30 = 2 rubber stamps / x

Let "x" be the cost of 2 rubber stamps.

We can set up a proportion to find "x" based on the given information:

10 rubber stamps cost $10.30

So, 1 rubber stamp costs $1.03

Therefore, 2 rubber stamps cost:

2 * $1.03 = $2.06

Thus, the equation to determine the cost of 2 rubber stamps is:

2x = $2.06

Dividing both sides by 2, we get:

x = $1.03

Let's assume that the cost of one rubber stamp is x dollars. Then, we can set up a proportion to solve for x:

10 rubber stamps cost $10.30, so:

10 stamps / $10.30 = 1 stamp / x

Simplifying this proportion by cross-multiplication, we get:

10 stamps × x = $10.30 × 1 stamp

10x = $10.30

Dividing both sides by 10, we get:

x = $1.03

Therefore, the cost of one rubber stamp is $1.03. To find the cost of two rubber stamps, we can multiply this amount by 2:

2 stamps × $1.03/stamp = $2.06

So the cost of 2 rubber stamps is $2.06.

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Percentage of change is increase and the percentage of change is 133.3%.

Change in percentage = changed percent × 100 / initial value

3/8 is changed into 7/8.

Change in value = 7/8 - 3/8 = 1/2

Change in percentage = 1/2 / 3/8 × 100

= 133.3%

Hence the percentage of change is increase and the percentage of change is 133.3%.

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The value of x in the photo is 1 inch.

We have,

Dimensions of the photo.

Length = 8 in

Width = 7 in

Dimension of the ad.

Length = 8 + x

Width = 7 + x

Now,

Area of the photo = 1/2 x area of the ad

8 x 7 = 1/2 (8 + x) (7 + x)

56 = 1/2 (8 + x) (7 + x)

112 = 56 + 8x + 7x + x²

x² + 15x + 56 - 112

Now,

To solve for x in the expression x² + 15x + 56 - 112, we first combine like terms:

x² + 15x + 56 - 112 = x² + 15x - 56

Now we can factor in the quadratic expression:

x² + 15x - 56 = (x + 16)(x - 1)

Setting this expression equal to zero, we get:

(x + 16)(x - 1) = 0

Using the zero product property, we know that this equation is true if either (x + 16) = 0 or (x - 1) = 0.

Therefore, the solutions for x are:

x + 16 = 0, which gives x = -16

or

x - 1 = 0, which gives x = 1

So the solutions for x are x = -16 and x = 1.

x = -16 (rejected)

Thus,

The value of x is 1.

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The absolute value of k is π/2.

To find the absolute value of k in the given probability density function f(x) = ksin(πy) if 0 < y < 1 and f(y) = 0 otherwise, follow these steps:

Recall that the total probability of a probability density function must equal 1. Therefore, we can write the equation as follows:

∫(from 0 to 1) f(y) dy = 1

Substitute f(y) with the given function:

∫(from 0 to 1) ksin(πy) dy = 1

Integrate the function with respect to y:

k[-cos(πy)/π] (from 0 to 1) = 1

Evaluate the integral at the limits:

k[-cos(π)/π + cos(0)/π] = 1

Simplify the expression:

k[-(-1)/π + 1/π] = 1

Solve for the absolute value of k:

k[2/π] = 1
k = π/2

The absolute value of k is π/2.

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Answer:

The sectarian violence is creating the situations leading to the fracturing of states. For example, in Syria, sectarian violence between Sunni and Shia Muslims has fueled a civil war that has led to the fracturing of the country. Similarly, in Iraq, sectarian violence between Sunni and Shia Muslims has contributed to the fracturing of the country, with ISIS taking advantage of the situation to establish a caliphate. The article also notes that sectarian violence has contributed to the instability of Lebanon and Bahrain.

Step-by-step explanation:

The minimum length of ribbon that Bradley needs is 50.24 cm.

To find the minimum length of ribbon Bradley needs to wrap around the circumference of the top of the basket, we can use the formula for the circumference of a circle, which is C = 2πr, where C is the circumference, r is the radius, and π (pi) is a constant approximately equal to 3.14.

So, for Bradley's basket, the radius is 8 centimeters, and the circumference would be:

C = 2πr = 2π(8) = 16π = 50.24

Therefore, the minimum length of ribbon Bradley needs is 50.24 centimeters. We can leave the answer in terms of π because it is an irrational number and cannot be expressed exactly as a decimal.

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There are some trigonometric functions such as tangent, cotangent, secant, and cosecant that have restricted ranges.

Parent functions that have a range of all real values are functions that can take on any possible output value in the real number system.

The functions that have a range of all real values include:

Constant function: f(x) = c, where c is any real number. Since the function is constant, it takes on the same value for every input, and therefore, the range is the set of all real numbers.

Linear function: f(x) = mx + b, where m and b are any real numbers. Since the graph of a linear function is a straight line, and it has a constant slope, the range is the set of all real numbers.

Quadratic function: f(x) = ax[tex]^2 + bx[/tex] + c, where a, b, and c are any real numbers, and a ≠ 0. Since the graph of a quadratic function is a parabola that opens upwards or downwards, and it can go arbitrarily high or low, the range is the set of all real numbers.

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The confidence interval for the population standard deviation is (5.39, 77.24).

To construct the confidence intervals for the population variance and population standard deviation, we will use the Chi-square distribution with n-1 degrees of freedom, where n is the sample size.

Given:

Sample size n = 20

Sample standard deviation s = 37

Confidence level c = 0.00 (which means we need to construct a 100% confidence interval)

First, we need to calculate the chi-square values for the lower and upper bounds of the confidence interval for the population variance:

chi-square lower = (n - 1) * s^2 / chi-square(0.5, n-1) = (20-1) * 37^2 / chi-square(0.5, 19) = 5966.45

chi-square upper = (n - 1) * s^2 / chi-square(1-0.5, n-1) = (20-1) * 37^2 / chi-square(0.5, 19) = 29.04

where chi-square(0.5, n-1) and chi-square(1-0.5, n-1) are the Chi-square values corresponding to the 0.5 and 0.995 quantiles, respectively, with n-1 degrees of freedom.

Therefore, the confidence interval for the population variance is (29.04, 5966.45).

Next, we can obtain the confidence interval for the population standard deviation by taking the square root of the bounds of the variance interval:

lower bound = sqrt(29.04) = 5.39

upper bound = sqrt(5966.45) = 77.24

Therefore, the confidence interval for the population standard deviation is (5.39, 77.24).

Note that the confidence interval for the population variance is wider than that for the population standard deviation because taking the square root reduces the spread of the interval.

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The conditional expectation of X given is E[X|X ≥ E[X]] is µ. The conditional variance is Var[X|X ≥ E[X]] is σ² of the Gaussian random variable X.

Given a Gaussian random variable X with mean µ and variance σ², we need to find the conditional mean and variance given X ≥ E[X].

First, we note that E[X] = µ and Var[X] = σ².

Next, we find the conditional probability P(X ≥ E[X])

P(X ≥ E[X]) = P(X - µ ≥ 0) = P(Z ≥ 0) = 0.5, where Z is the standard normal distribution.

Using Bayes' theorem, we can write the conditional mean and variance as

E[X|X ≥ E[X]] = µ + σφ(Z)/P(X ≥ E[X])

Var[X|X ≥ E[X]] = σ²[1 - φ(Z)²]/P(X ≥ E[X]),

where φ(Z) is the standard normal probability density function.

Substituting the values, we get

E[X|X ≥ E[X]] = µ + σφ(0)/0.5 = µ

Var[X|X ≥ E[X]] = σ²[1 - φ(0)²]/0.5 = σ²

Therefore, the conditional mean and variance given X ≥ E[X] are both equal to the original mean µ and variance σ² of the Gaussian random variable X.

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A) The probability of a z-score greater than 1.6189 is 0.0523, P(X > 142.7) = 0.0523.

B)  The probability of a z-score greater than 2.2145 is 0.0135, P(M > 142.7) = 0.0135.

a) Using the z-score formula, we have:

Looking up the z-table, we find the probability of a z-score greater than 1.6189 is 0.0523.

Therefore, P(X > 142.7) = 0.0523.

b) The mean of the sample mean distribution is still μ = 138.1, but the standard deviation is now σ/√n = 30.7/√216 ≈ 2.0894.

Using the central limit theorem, we can approximate the sample mean distribution as a normal distribution.

Looking up the z-table, we find the probability of a z-score greater than 2.2145 is 0.0135.

Therefore, P(M > 142.7) = 0.0135.

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this is a special triangle so the undefined lenght is 12

so the answer is 12/20 = 0.6

The force that is between two 0. 004 c charges that are 0. 35 m apart in air is 1, 174.2 N.

The force between these charges can be found by Coulomb's Law which states that the electric force linking two charged particles is proportional to both their individual quantitative charge and inversely proportionate to the square of their separation distance.

Given charges of 0. 004 c and 0. 35 m apart, the formula shows :

F = (8. 99 x 10 ⁹ N m ² /C² x | 0. 004 C x 0. 004 C| ) / ( 0. 35 m ) ²

F = 143.84  / 0.1225

F = 1, 174.2 N

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The probability of taking at least four trials to find the first defective light bulb is 0.073 (rounded to 3 decimal places).

To find the probability of taking at least four trials to find the first defective light bulb, we can use the geometric distribution formula:
P(X >= k) = (1-p)^(k-1) * p
Where X is the number of trials needed to find the first defective light bulb, p is the probability of finding a defective bulb on any given trial, and k is the minimum number of trials required.
In this case, we want to find the probability of taking at least four trials, so k = 4. We also know that the probability of finding a defective bulb on any given trial is 0.1 (since there is a 10% chance of any given bulb being defective). Therefore, we can plug in these values:
P(X >= 4) = (1-0.1)^(4-1) * 0.1
P(X >= 4) = 0.729 * 0.1
P(X >= 4) = 0.0729
So the probability of taking at least four trials to find the first defective light bulb is 0.073 (rounded to 3 decimal places).

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Using the distance formula, the perimeter of the quadrilateral PQRS is equal to 15.6 to the nearest tenth.

The distance formula is a mathematical equation used to find the distance between two points in a plane. It is given by the following formula:

d = √[(x₂ - x₁)² + (y₂ - y₁)²],

where d is the distance between the points (x₁, y₁) and (x₂, y₂).

we shall evaluate the distance between the points PS and QR as follows:

distance between P and S = √[[1 - (-3)]² + (1 - 3)²]

distance between P and S = √20

distance between P and S = 4.5

distance between Q and R = √[[1 - (-3)]² + [-1 - (-2)]²]

distance between Q and R = √17

distance between Q and R = 4.1

Thus; PQ =5, SR = 2, PS = 4.5, and QR = 4.1

perimeter of quadrilateral PQRS = 5 + 2 + 4.5 + 4.1

perimeter of quadrilateral PQRS = 15.6.

Therefore, using the distance formula, the perimeter of the quadrilateral PQRS is equal to 15.6 to the nearest tenth.

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The instantaneous rate of change of the supply of bicycle helmets with respect to price when the price is $66 is 0.16 helmets per dollar.

The supply of bicycle helmets as a function of price can be represented by the equation S(p) = 85p² - 26p + 395, where p is the price in dollars. To find the instantaneous rate of change of the supply with respect to price at a particular price point, we need to take the derivative of the supply function with respect to price and evaluate it at that price point.

So, taking the derivative of S(p) with respect to p, we get:

S'(p) = 170p - 26

Evaluating this expression at p = 66, we get:

S'(66) = 170(66) - 26 = 11294

This means that at a price of $66, the supply of bicycle helmets is increasing at a rate of 11294 helmets per dollar.

However, we are asked to round to the nearest hundredth, so we divide by 100 to get:

S'(66) ≈ 112.94 helmets per dollar

Rounding to two decimal places, we get:

S'(66) ≈ 0.16 helmets per dollar

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To calculate the selling price of the house, we can use the formula for a mortgage:

M = P [ i(1 + i)^n ] / [ (1 + i)^n – 1]

Where:
M = monthly payment
P = principal (selling price)
i = interest rate per month (4.5%/12)
n = total number of payments (30 years x 12 months)

We know that the monthly payment is $811 and the total number of payments is 30 years x 12 months = 360 months. So we can solve for the principal:

$811 = P [ (0.045/12) (1 + 0.045/12)^360 ] / [ (1 + 0.045/12)^360 – 1]

$811 = P [ 0.00375 (1 + 0.00375)^360 ] / [ (1 + 0.00375)^360 – 1]

$811 = P [ 0.00375 (3.8113) ] / [ 3.8113 – 1]

$811 = P [ 0.014287 ]

P = $56,732.77

Therefore, the selling price of the house was $56,732.77.

To calculate the total interest paid over 30 years, we can use the formula:

Total interest = (monthly payment x total number of payments) - principal

Total interest = ($811 x 360) - $13,694

Total interest = $292,740 - $13,694

Total interest = $279,046

Therefore, they will pay a total of $279,046 in interest over 30 years.

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No. There is enough evidence to reject the claim that the mean number of visits per year is 5.8. So, the correct option is, option B)

To determine if it can be concluded that the average number of visits per year is still 5.8, we need to perform a hypothesis test.

Let's define the null and alternative hypotheses as follows:

Null hypothesis (H0): The population mean number of visits per year is 5.8.

Alternative hypothesis (Ha): The population mean number of visits per year is not 5.8.

We will use a two-tailed t-test with a significance level of 0.05 to test the hypothesis.

Sample mean = (3+4+6+3+6+3+2+3+4+5+5+2+3+2+0+4+4+3+3+4) / 20 = 3.6

Sample standard deviation (s) = 1.493

Next, we can calculate the t-value:

t = (mean - μ) / (s / sqrt(n))

t = (3.6 - 5.8) / (1.493 / sqrt(20))

t = -3.156

Using a t-distribution table with 19 degrees of freedom (df = n - 1 = 20 - 1), the critical values for a two-tailed test at a 0.05 level of significance are ±2.093.

Since our calculated t-value (-3.156) is outside the critical values, we can reject the null hypothesis.

Therefore, there is enough evidence to reject the claim that the mean number of visits per year is 5.8 at the 0.05 level of significance.

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Answer:

Solving for y

exact form for y = 4/3

Demical form for y = 1/3

Mixed number for y = 1 1/3

( BTW all of these answers all right it juts depends on what exactly there asking for, for example if there asking for the exact form for y it would be 4/3 )

You would expect have 5 CDs to be rap in the next 30 CDs

From the question, we have the following parameters that can be used in our computation:

pop 65

rock 10

rap 15

This means that we have the following proportion

Rap = 15/(65 + 10 + 15)

Evaluate

Rap = 15/90

So, we have

Rap = 1/6

Considering loaning 30 CDs out, we have

Rap = 1/6 * 30

Rap = 5

Hence, the expected values of rap CDs is 5

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The volume of the solid generated by revolving the region bounded by the lines and curves about the x-axis is 2π(1 - e⁻¹) cubic units.

To find the volume of the solid generated by revolving the region bounded by the lines and curves about the x-axis, we need to use the method of cylindrical shells.

The volume can be calculated using the following formula:

V = ∫[a,b] 2πx f(x) dx

where a=0, b=1, and f(x) = e^(-x).

Substituting the given values, we get:

[tex]V = \int[0,1] 2\pi x e^{(-x)} dx[/tex]

Using integration by parts, we can solve this integral and get:

[tex]V = 2 \pi[e^{(-x)} - x e^{(-x)}][/tex] from 0 to 1

Simplifying this, we get:

V = 2π(1 - e⁻¹)

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Answer:

The tip is $17.00, and the cost of the meal is $62.50. To find the percentage that the tip represents of the cost of the meal, we need to divide the tip by the total cost and multiply by 100:

Percentage tip = (tip / total cost) x 100%

Percentage tip = (17.00 / (62.50 + 17.00)) x 100%

Percentage tip = (17.00 / 79.50) x 100%

Percentage tip = 0.214 x 100%

Percentage tip = 21.4%

Rounding to the nearest tenth of a percent, the tip represents 21.4% of the cost of the meal.

The tip is approximately 21.4% of the meal cost.

To find the percentage of the cost that is the tip, we need to first calculate the actual amount of the tip and then express it as a percentage of the meal cost.

The amount of the tip is $17.00, and the cost of the meal is $62.50, so the total amount paid is:

$62.50 + $17.00 = $79.50

To find the percentage of the cost that is the tip, we can use the formula:

(tip amount / total amount) x 100%

Plugging in the values we have:

($17.00 / $79.50) x 100% ≈ 21.4%

Rounding to the nearest tenth of a percent, we get:

21.4%

Therefore, the tip is approximately 21.4% of the meal cost.

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1. For the Midwest region, the average number of sales orders per representative for the group that had training is 0.76 more than the average number of sales per representative for the group that had no training.

2. For the Northeast region, the average number of sales orders per representative for the group that had training is 1.48 more than the average number of sales per representative for the group that had no training.

3. The data from the sales director’s study indicates that the one-month training program  Increases sales.

To calculate the average number of sales orders per representative in the Midwest region, we say

234/50  - 196/50

= 4.68 - 3.92

= 0.76

The questions asked are based on the situation below;

For three months after the training program, the sales director collected the sales data for 200 representative from the Midwest and Northeast region. The director then broke down the number of sales orders for the representative according to whether they received training or not. This data is shown in the table

                             Three months sales orders

                                          Training                    No training

Midwest                                   234                              196

Northeast                                252                               178

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The function graphed on the axes above should be expressed as a piecewise function as follows;

f(x) = -3x - 8    {x ≤ -2}

    = 6x - 17     {x > 3}

In order to determine the piecewise function, we would determine an equation that represent each of line shown on the graph. Therefore, we would determine the slope of this line;

Slope (m) = (y₂ - y₁)/(x₂ - x₁)

Slope (m) = (4 + 2)/(-4 + 2)

Slope (m) = 6/-2

Slope (m) = -3.

At data point (-2, -2) and a slope of -3, a linear equation for this line can be calculated by using the point-slope form as follows:

y - y₁ = m(x - x₁)

y + 2 = -3(x + 2)  

y = -3x - 8

For the second line, we have:

Slope (m) = (7 - 1)/(4 - 3)

Slope (m) = 6/1

Slope (m) = 6.

At data point (3, 1) and a slope of 6, a linear equation for this line can be calculated by using the point-slope form as follows:

y - y₁ = m(x - x₁)

y - 1 = 6(x - 3)  

y = 6x - 17

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Answer: What is the question?

Step-by-step explanation:

Brainliest pls:)

The distance between the robin and the base of the pole is 6.77 meters

To determine the distance, we need to know the different trigonometric identities in mathematics.

These identities are given as;

From the information given, we have that;

The angle of depression, θ = 38 degrees

The distance is unknown

The hypotenuse side is 11 meters

Now, using the sine identity, we have;

sin 38 = d/11

Cross multiply the values

d = 0. 6156(11)

multiply the values

d = 6. 77 meters

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Superman's average rate is  50 meters per second. Every 12 second superman flies 600 meters. Superman is 900 meters from Lois.

To find Superman's average rate, we need to find the change in distance divided by the change in time:

Average rate = (change in distance) / (change in time)

From 6 seconds to 9 seconds, Superman travels a distance of 1800 - 1650 = 150 meters. So the change in distance is 150 meters, and the change in time is 9 - 6 = 3 seconds.

Average rate = (150 meters) / (3 seconds) = 50 meters per second

To find how far Superman flies in 12 seconds, we can use the average rate:

Distance = (average rate) x (time)

Distance = (50 meters per second) x (12 seconds) = 600 meters

To find how close Superman is to Lois after 21 seconds, we need to use the same formula again, using the new distance and time values:

Distance = (average rate) x (time)

From 6 seconds to 21 seconds, Superman travels a distance of 1800 - x, where x is the distance he is from Lois after 21 seconds. So the change in distance is (1800 - x) - 1800 = -x, and the change in time is 21 - 6 = 15 seconds.

Average rate = (-x meters) / (15 seconds) = -x/15 meters per second

We don't know the value of x yet, but we can use the average rate and the formula for distance to set up an equation:

x = (average rate) x (time) + initial distance

x = (-x/15 meters per second) x (15 seconds) + 1800 meters

Simplifying this equation gives:

x = 1800 / 2 = 900 meters

So after 21 seconds, Superman is 900 meters from Lois.

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