Only $28.25 are available. After Lena uses the card for 15 minutes of calls, there are still 28.25 credits left.
Given that,
Lena spent $30.50 on a prepaid phone card. With this card, calls cost 15 cents each minute. the amount of credit, c (in dollars), remaining on the card following x minutes of calls
It can be written as,
C(x) = 30.50 - 0.15x
C(x) = 30.50-(0.15 x 15)
after Lena uses it for 15 minutes,
C(x) = 30.50 – 2.25 = $28.25 in remaining credits.
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7x+12=x-6 please answer
Answer:
x=-3
Step-by-step explanation:
Pls help i domt get this
Answer:
[tex]5^{15}[/tex] × 120 = 30,517,578,125 × 120
Step-by-step explanation:
suppose you sell hats for 10 dollars each and sunglasses for 5 dollars each. you know the expected number of hats sold in a day is 10 with standard deviation 1; you know the expected number of sunglasses sold in a day is 20 with standard deviation 2; you know the sale of hats and sunglasses are independent. what is the standard deviation of your revenues in a day? (round to closest dollar)
Answer:
2
Step-by-step explanation:
because average of 1 and 2 is 1.5 rounded is 2
The standard deviation of your revenues in a day is 14.
What is a standard deviation?The square root of the variance is used to calculate the standard deviation, a statistic that expresses how widely distributed a dataset is in relation to its mean.
Let x be the revenue from hats.
And let y be the revenue from sunglasses.
And z be the total revenue.
Then according to the question:
z = 10x + 5y
You know the expected number of hats sold in a day is 10 with standard deviation 1.
σₓ = 1
σy = 2
Taking squares of both of the equation.
σₓ² = 1² = 1
σy² = 2² = 4
To find the standard deviation of your revenues in a day:
V(z) = (10)²σₓ² + 5²σy²
V(z) = (100)(1) + (25)(4)
V(z) = 200
Standard deviation,
σz² = √(200)
σz² = 10√(2)
σz² = 14.14
σz² ≈ 14
Therefore, the required standard deviation is 14.
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given the following expressions1. -5/8+3/52. 1/2+ √23. (√5)×(√5)4. 3×(√49)which expression(s) will result in an irrational number.(1) only 2(2) only 3(3) 1,3,4(4) 2,3,4
1) Only 2
1) Examining the expressions we have
1. -5/8+3/5 =-1/40 Rational Expression
2. 1/2+ √2 Irrational Expression
3.(√5)×(√5)= 5 Rational Expression
4. 3×(√49) = 21 Rational Expression
2) Since √2 is an irrational number √2 = 1.4142.... non-periodic and infinite number, and number added to it will yield an irrational number.
3) So the answer is 1) Only 2
If f (x) = 4x2 + 3x − 5, then the quantity f of the quantity x plus h end quantity minus f of x end quantity all over h is equal to which of the following?
4 times the quantity x plus h end quantity squared plus 3 times the quantity x plus h end quantity minus 5 minus 4 times x squared plus 3 times x minus 5 all over h
4 times the quantity x squared plus 2 times x times h plus h squared end quantity plus 3 times the quantity x plus h end quantity minus 5 minus the quantity 4 times x squared plus 3 times x minus 5 end quantity all over h
the quantity 4 times x plus 4 times h end quantity squared plus the quantity 3 times x plus 3 times h end quantity minus 5 minus the quantity 4 times x squared plus 3 times x minus 5 end quantity all over h
4 times the quantity x plus h end quantity squared plus 3 times x minus 5 minus 4 times x squared minus 3 times x plus 5 all over h
The difference quotient of f(x) is:[ f(x + h) - f(x)]/h = 8x + 4h + 3
How to get the difference quotient?Here we have the function:f(x) =4x^2 +3x - 5
And we want to get the difference quotient that can be written as:
[f(x + h) - f(x)]/h
Replacing the function we get:
[f(x + h) - f(x)]/h = [4*(x + h)^2 + 3*(x + h) - 5 - 4*x^2 - 3x + 5]/h
Solving further (open the brackets), we have
[f(x + h) - f(x)]/h = [4x^2 + 8*x*h + 4h^2 + 3x + 3h -5 - 4x^2 - 3x + 5]/h
Evaluate the like terms
So, we have
[f(x + h) - f(x)]/h = [8*x*h + 4h^2 + 3h]/h
Evaluate the quotients
[f(x + h) - f(x)]/h = 8x + 4h + 3
That is the difference quotient.
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Miss Young is bringing cookies and brownies in for one of her classes. She has to bring
a total of 26 desserts. She pays $0.65 for each cookie and $0.90 for each brownie.
Using a system of equations, supposing that she spent $19.65, the amounts are as follows:
Cookies: 15.Brownies: 11.What is a system of equations?A system of equations is when multiple variables are related, and equations are built to find the numeric values of each variable, according to the relations built in the context of this problem.
For this problem, the variables are defined as follows:
Variable x: number of cookies purchased.Variable y: number of brownies purchased.She brought a total of 26 desserts, hence:
x + y = 26.
She spent a total of $19.65, hence, considering the price of each item:
0.65x + 0.9y = 19.65.
From the first equation, we have the following relation:
y = 26 - x.
Hence, replacing in the second, we can solve for x as follows:
0.65x + 0.9(26 - x) = 19.65
0.25x = 3.75
x = 3.75/0.25
x = 15 cookies.
Then the number of brownies is found as follows:
y = 26 - 15 = 11 brownies.
Missing informationWe suppose that she spent $19.65, and that the problems asks for the amounts of cookies and brownies purchased.
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What is the transformation of both y=-√-4x, and y=√-4x? I've looked everywhere to try and find it, but the internet is not helping!
The transformation that relates the two functions:
f(x) = y = -√(-4x)
g(x) = y = √(-4x)
Is a reflection across the x-axis.
What is the transformation applied?
We define a reflection across the x-axis as a transformation that does a "vertical reflection" along the line y = 0 (which is the x-axis).
For a function f(x), a reflection across the x-axis generaste the new function g(x) that can be written as:
g(x) = -f(x).
In this case the original function is:
f(x) = y = -√(-4x)
And the transformed function is:
g(x) = y = √(-4x)
You can see that the only difference is the sign, such that we can write:
g(x) = -f(x) = -(-√(-4x)) = √(-4x)
So we conclude that the transformation is a reflection across the x-axis.
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what is the answer to 2y=3x+4
Answer:
y = (3/2)x + 2
assuming that the question is to find y in its simplest form.
Step-by-step explanation:
2y=3x+4
(1/2)*(2y)= (1/2)*(3x+4)
y = (3/2)x + 2
Each gallon of paint covers 200 square feet. I have to paint one side of a wall that is 12 meters tall and 80 meters long. If a foot is approximately 0.3084 meters, then what is the smallest whole number of gallons I can buy and have enough paint to cover the whole wall
Answer:
1 ft ≈ 0.3048 m
1 ft2 ≈ 0.09290304 m2
200 ft2 ≈ 18.580608 m2
Step-by-step explanation:
The total surface area to paint = 12 m * 80 m = 960 square meters
1 ft ≈ 0.3048 m
1 ft2 ≈ 0.09290304 m2
200 ft2 ≈ 18.580608 m2
And so one gallon of paint covers about 18.581 square meters.
960 m2 / ( 18.581 m2 per gallon) ≈ 51.67 gallons
So 51 gallons would not be enough... it would take 52 gallons of paint to cover the wall.
The point where the graphs of two equations intersect has y-coordinate 2. One equation is y = -3 = 5. Find the other equation if its graph has a slope of 1.
The equation of the line for the given slope 1 is y= x + 2
Equation of the line:
An equation of the line refers the algebraic form of representing the set of points, which together form a line in a coordinate system.
Given,
The point where the graphs of two equations intersect has y-coordinate 2. One equation is y = -3x + 5.
Here we need to find the other equation if its graph has a slope of 1.
We know that, the general representation of equation of line is y= ax + b
where a is the slope and b is the y intercept.
Through the given details we know that the slope of the line is 1 and why is point where two lines intersect hence, it is the intercept.
And the intercept value is 2.
Therefore, the equation of the other line is y= x + 2
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someone please help me please
Graph
[tex]-2x+y\ge-2[/tex]
Procedure
A 21-foot beam is to be cut into three pieces so that the second and third piece are each 3 times the length of the first piece. If X represents represents the length of the first piece find the length of each piece.
The length of the first piece is 3 inches, and the second and third pieces are each 9 inches
What are Arithmetic operations?Arithmetic operations can also be specified by subtracting, dividing, and multiplying built-in functions.
Given that a 21-foot beam is to be cut into three pieces so that the second and third pieces are each 3 times the length of the first piece.
We have to determine the length of each piece.
Let x represents the length of the first piece
As per the given condition,
x + 3x + 3x = 21
7x = 21
x = 21 / 7
x = 3
Thus, the first piece is 3 inch
So 2nd piece is 3×3 = 9 inches ( 3 times to first piece )
And 3rd piece is 3×3 = 9 inches ( 3 times to first piece )
Therefore, the length of the first piece is 3 inches, and the second and third pieces are each 9 inches
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5/b= 3/b-6
first i cross multiplied as i’m supposed to go and got the answer
5b-30=3b
what steps are next?
How do you solve this
Answer: wut
Step-by-step explanation: wut
stack of mail consists of 8 bills, 10 letters, and 6 advertisements. One piece of mail is drawn at random and put aside. Then a second piece of mail is drawn. Find P (both are letters)
INFORMATION:
We know that:
- stack of mail consists of 8 bills, 10 letters, and 6 advertisements.
- One piece of mail is drawn at random and put aside. Then a second piece of mail is drawn.
And we must find P (both are letters)
STEP BY STEP EXPLANATION:
To find the probability, we need to know that we have two events. First, when one piece of mail is drawn at random and put aside and, second, when a second piece of mail is drawn.
These two events are dependent. If A and B are dependent events, P(A and B) = P(A) • P(B after A) where P(B after A) is the probability that B occurs after A has occurred.
So, first
- Probability of A (the first piece is letter)
[tex]P(A)=\frac{favorable\text{ }cases}{total\text{ cases}}=\frac{10}{24}[/tex]- Probability of B after A
Since A already occurred and one piece of the mail was drawn (a letter), now in total we would have 9 letter and 23 total pieces
[tex]P(B\text{ after }A)=\frac{9}{23}[/tex]Finally, replacing in the initial formula
[tex]P(A\text{ and }B)=\frac{10}{24}\cdot\frac{9}{23}=\frac{90}{552}=0.1630[/tex]Finally, the probability would be 0.1630
ANSWER:
P (both are letters) = 0.1630
which hill's criteria, addressing whether the exposure comes before or after the effect, is the only criteria that must be met 100% for a causal relationship to be possible?
Hill's Criteria of Strength is the only criteria that must be met 100% for a causal relationship to be possible.
The Criteria of strength is Hill's first test for causation. He stated that the likelihood of an association being causative increases with the size of the connection between exposure and disease. Hill used Percival Pott's investigation into the prevalence of scrotal cancer in chimney sweeps to highlight this issue. Since the correlation between that occupation and sickness was so strong (almost 200 times more than in other jobs), it was concluded that chimney soot was probably a contributing factor. On the other hand, Hill argued that minor connections are less indicative of causation since they are more likely to be explained by other underlying factors (such as bias or confounding).
To evaluate possibly causative associations, it is essential to define what is meant by a "strong" correlation. Scientists may now distinguish between strong and weak associations using more mathematically sound criteria than Hill had in mind because of developments in statistical theory and computing capacity. Strength is no longer just understood as an association's magnitude. Furthermore, multi-factorial disorders and the existence of determinant risk variables that are tiny in magnitude but statistically significant have received more attention from researchers. The recognized standard for determining the strength of an observed correlation and, hence, its potential causation, is statistical significance today rather than the magnitude of the association.
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Which of the following is equivalent to 1-2x > 3(x - 2)?
01-2x > 3x - 7
01-2x > 3x - 6
01-2x > 3x - 2
01-2x > 3x - 5
POSSIBLE POINTS:
Answer: 01-2x > 3x - 6
Step-by-step explanation: distributive property
What is the answer to the following calculation, rounded to the correct number of significant figures?100.000 g+ 75.0 g
Answer:
175g
Step-by-step explanation:
100.000g+75.0g= 175g
ps. pls give brainliest answer :)
The sum of the numbers 100.000g and 75.0g in expression is 175g.
What are mathematical operations?Calculate the answer using a math operator is referred to as a mathematical operation.
Basic mathematical operations are addition, multiplication, subtraction and division.
The given numbers are,
100.000g and 75.0g
The zeros can be neglected after decimal points,
So the numbers can be written as,
100g and 75g.
To find the required expression, add 100g and 75g.
100g + 75g = 175g.
The required sum of the numbers is 175g.
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Solve for x.
3.5x=31.5
Answer:
x = 9
Step-by-step explanation:
x = 31.5 / 3.5
x = 9
Answer:
x = 9
Step-by-step explanation:
since 3.5 is being multiplied by x to get 31.5 to get rid of it and leave x by itself you have to divide both sides by 3.5
(3.5x)/(3.5)= (31.5)/(3.5)
x=9
Express 35 as a fraction of 95. Give your answer in its simplest form.
Answer:
=35/95
=(5 x7)/95
=5 x 7/5 x 19
=7/19
Whats the answer to this -11 + 2x
A.-10
B.9
C.-12
D.6
(a+6)-(a+2)Simplify
Answer: 4
[tex]\sqrt{x} ^2+2x-3[/tex]
The result of the expression given is 3x - 3
Simplification of Linear EquationTo solve this problem, we have to simplify the equation, and write the expression.
Given that
[tex]\sqrt{x^2}+ 2x -3[/tex]
For every square root having a square inside, they both cancel out each other to have the variable only.
Lets apply that in this expression
[tex]\sqrt{x^2} + 2x - 3\\x + 2x - 3[/tex]
To solve the expression, we would have the final answer to the question.
[tex]x + 2x - 3\\3x - 3[/tex]
The value of the expression given is 3x - 3
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y = 2x + 3
when x = -1, y =
Answer: y = 1
Step-by-step explanation:
y = 2(-1) +3
y = -2 + 3
y = 1
Find the value of x.
(8x - 11)
5x°
(2x+6)°
Answer: x=37/3
Step-by-step explanation:
8x-11+5x+2x+6=180 ==> three angles of a triangle add up to 180 degrees
8x+5x+2x-11+6=180
13x+2x-5=180
15x-5=180
15x=185
x=185/15
x=37/3
Solve 4- 3x = 6 - 5x
X =
Answer:
Step-by-step explanation:
4 - 3 x = 6 - 5 xx
[tex]-3x+4=6-5xx^{2}[/tex]
x = 1
x = - [tex]\frac {2}{5}[/tex]
Answer:
x=1
Step-by-step explanation:
sense x's are on both sides you need to bring one of them over, add 3x to both sides to get 4=6-2x , then subtract 6 from each side to get -2=-2x , then to get x by itself divide both sides by -2 to get 1=x
Hemework -13 .
Express the ratio 20cm to 15m in the form 1:n
Answer:
1: 75
Step-by-step explanation:
20cm : 15m
Convert meters to cm
1 meter = 100 cm
15m = 15 x 100 = 1500 cm
20cm:1500cm
Divide both sides of the ratio by 20
=> 1 : 1500/20 = 1: 75
The ratio of 20cm to 15m in the form 1:n is 1:75.
What is a ratio?A ratio is a mathematical comparison of two or more quantities expressed in terms of the number of times one quantity contains another quantity.
It is used to express the relationship between two or more numbers or variables and is usually written as a fraction or with a colon between the two numbers.
We have,
First, we need to convert both measurements to the same unit.
Let's convert 20cm to meters:
20 cm = 20/100 m = 0.2 m
Now we can express the ratio of 20cm to 15m as:
0.2m : 15m
To simplify this ratio, we can divide both sides by the greatest common factor of the two numbers, which is 0.1m:
0.2m/0.1m : 15m/0.1m
2 : 150
Finally, we can simplify the ratio by dividing both sides by 2:
1 : 75
Therefore,
The ratio of 20cm to 15m in the form 1:n is 1:75.
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Which of the following is true?
A function is a reletion with one output for each input. Then, in a ordered pair inputs and outputs represent a relationship between two values.
Some relationships make sence (one output for each input) and others dont't.
Functions are relationsips that make sence.
All functions are relations, but not all relations are functionsExperimental and theoretical see pic
1) Wrong statement:
The difference between the experimental and theoretical probability is 1/10
Correct statement:
The difference between the experimental and theoretical probability is 3/200
2) Wrong statement:
The difference between the experimental and theoretical probability is 1/10
Correct statement:
The difference between the experimental and theoretical probability is 3/200
Explanation:N(Pennies) = 6
N(Nickels) = 8
N(Dimes) = 4
N(quarters) = 7
N(total) = 6 + 8 + 4 + 7
N(total) = 25
1) The theoretical probability of selecting a dime = 4/25
The experimental probability of selecting a dime = 30/150 = 1/5
B is wrong because theoretical probability is 4/25, not 9/50
Wrong statement:
The theoretical probability of selecting a dime is
Correct statement:
The theoretical probability of selecting a dime is 4/25
2) The experimental probability of selecting a penny = 45/200 = 9/40
The theoretical probability of selecting a penny = 6/25
Difference between experimental and theoretical probability = 6/25 - 9/40
Difference between experimental and theoretical probability = 3/200
Wrong statement:
The difference between the experimental and theoretical probability is 1/10
Correct statement:
The difference between the experimental and theoretical probability is 3/200
A software company in Burlington used to bill clients $214.79 per hour for work done by its consultants. The company recently adjusted its rates and now charges the same amount. What was the percent of decrease in the billing rate?
The percent of decrease in the billing rate is 2.37%.
How to calculate the percentage?It should be noted that a percentage decrease is calculated as
= Decrease in value / Initial value × 100
Let's assume the following:
Initial amount = $220
New amount = $214.79
Decrease in amount = $220 - $214.79 = $5.21
The percentage decrease will be:
= 5.21 / 220 × 100
= 2.37%
The question is incomplete and the values were assumptions.
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