Answer:
3n + 12 = 45
Step-by-step explanation:
3n + 12 = 45
3n = 45 - 12
3n = 33
n = 33
3
n = 11
Answer:
3n + 12 = 45
Step-by-step explanation:
*Process of elimination*
___________________
3n + 12 = 45
(given)
_________
3n + 12 = 45
- 12 - 12
(subtraction property of equality)
__________________________
3n = 33
÷ 3 ÷ 3
(division property of equality)
_______________________
n = 11
_____
7n - 8 = 62
(given)
________
7n - 8 = 62
+ 8 + 8
(addition property of equality)
__________________________
7n = 70
÷ 7 ÷ 7
(division property of equality)
_______________________
n = 10 ≠ 11
________
8n + 6 = 102
(given)
________
8n + 6 = 102
- 6 - 6
(subtraction property of equality)
__________________________
8n = 96
÷8 ÷8
(division property of equality)
_______________________
n = 12 ≠ 11
________
5n - 20 = 25
(given)
________
5n - 20 = 25
+ 20 + 20
(addition property of equality)
__________________________
5n = 45
÷5 ÷5
(division property of equality)
_______________________
n = 9 ≠ 11
You measure the period of a mass oscillating on a vertical spring ten times as follows:
Period (s): 1.06, 1.31, 1.28, 0.99, 1.48, 1.37, 0.98, 1.31, 1.59, 1.55
Required:
What are the mean and (sample) standard deviation?
a. Mean: 1.228, Standard Deviation: 0.2135
b. Mean: 1.325, Standard Deviation: 0.1674
c. Mean: 1.292. Standard Deviation: 0.2211
d. Mean: 1.228, Standard Deviation: 0.2098
e. Mean: 1.292, Standard Deviation: 0.2135
Answer:
Step-by-step explanation:
Mean is the ratio of sum of the dataset to the sample size. Mathematically:
[tex]\overline x = \frac{\sum Xi}{N}[/tex]
Xi are the individual periods
N is the sample size
[tex]\sum Xi = 1.06+1.31+1.28+0.99+1.48+1.37+0.98+1.31+1.59+1.55\\\sum Xi = 12.92[/tex]
N = 10
Substitute
[tex]\overline x = \frac{12.92}{10}\\\overline x = 1.292[/tex]
hence the mean of the samples is 1.292
For the standard deviation:
[tex]\sigma = \sqrt{\frac{\sum (x-\overline x)^2}{N} } \\[/tex]
[tex]\sum (x-\overline x)^2 = (1.06-1.292)^2+ (1.31-1.292)^2+ (1.28-1.292)^2+ (10.99-1.292)^2+ (1.48-1.292)^2+ (1.37-1.292)^2+ (0.98-1.292)^2+ (1.31-1.292)^2+ (1.59-1.292)^2+ (1.55-1.292)^2\\\sum (x-\overline x)^2 = 0.43996[/tex]
Substitute into the formula:
[tex]\sigma = \sqrt{\frac{0.43996}{10} }} \\\sigma = \sqrt{{0.043996}}} \\\sigma = 0.2098[/tex]
Hence the standard deviation is 0.2098
anyone in flvs? we should find each other in live lessons lol
Answer:
nope
Step-by-step explanation:
Michael exercises more than 35 minutes per day.
Use t to represent Michael's amount of exercise (in minutes per day).
Answer:
t>35
Step-by-step explanation:
Since Michael exercises more than 35 days, t is greater than 35. To express that in an inequality, the answer is t>35. Hope this helped!
Which equation shows the variable terms isolated on one side and the constant terms isolated on the other side for the
equation 3x-5=-2x+ 10?
A. X=5. B.—5=x. C.—15=—5x. D.—5x=15
Answer:
A; (X=5)
Step-by-step explanation:
Move the constants and variable terms to one side:
3x-5= -2x+10
-5+10= -2x+ 3x
Combine like terms:
5=x or x=5
Answer:
The answer is C
Step-by-step explanation:
If you take the equation and simplify it.
3x-5=-2x+10
You would minus 3x from both sides, leaving the equation like
-5=-5x+10
Then you would minus 10 from both sides, leaving the equation like
-15=-5x
If you wanted to go further you could divide both sides by -1 and get rid of the negatives. Leaving the equation like
15=5x
Then to put it into the simpleist form you would divide both sides by 5, leaving the equation like
3=x
I hope this helps.
Your teacher invented another game: You will pick one card from a deck of cards. If
you pick a heart, you will win $25.00. Otherwise, you will lose $5.00.
From the standpoint of the player, what is the expected value of this game?
Enter expected value
What does the expected value tell us about the game?
O The game is good to play, you will make money on average.
O The game is NOT good to play, you will tend to lose money.
O It doesn't matter if you play, you will generally break even.
Answer:
C
Step-by-step explanation:
A man walks along a straight path at a speed of 4 ft/s. A searchlight is located on the ground 20 ft from the path and is kept focused on the man. At what rate is the searchlight rotating when the man is 15 ft from the point on the path closest to the searchlight
Answer:
0.128rad/sec
Step-by-step explanation:
Let x represent the between the man and the point on the path
θ = the angle
dx/dt = 4 ft/s
dθ/dt = rate is the searchlight rotating when the man is 15 ft from the point on the path closest to the searchlight
tan θ = x/20 ft
Cross Multiply
20tan θ = x
dx/dt = 20sec² θ dθ/dt
dθ/dt = 1/20 × cos² θ dx/dt
dθ/dt= 1/20 × cos² θ × 4
dθ/dt = 1/5 × cos² θ
Note : cos θ = 4/5
dθ/dt = 1/5 × (4/5)²
dθ/dt = 16/125
dθ/dt = 0.128rad/sec
Which ordered pair, if included in this relation, would cause it to no
longer be a function?
Answer:
(-6,3)
Step-by-step explanation:
the half life of c14 is 5730 years. Suppose that wood found at an archeological excavation site contains about 35% as much C14 as does living plant material. Determine when the wood was cut
Answer:
The wood was cut approximately 8679 years ago.
Step-by-step explanation:
At first we assume that examination occured in 2020. The decay of radioactive isotopes are represented by the following ordinary differential equation:
[tex]\frac{dm}{dt} = -\frac{m}{\tau}[/tex] (Eq. 1)
Where:
[tex]\frac{dm}{dt}[/tex] - First derivative of mass in time, measured in miligrams per year.
[tex]\tau[/tex] - Time constant, measured in years.
[tex]m[/tex] - Mass of the radioactive isotope, measured in miligrams.
Now we obtain the solution of this differential equation:
[tex]\int {\frac{dm}{m} } = -\frac{1}{\tau}\int dt[/tex]
[tex]\ln m = -\frac{1}{\tau} + C[/tex]
[tex]m(t) = m_{o}\cdot e^{-\frac{t}{\tau} }[/tex] (Eq. 2)
Where:
[tex]m_{o}[/tex] - Initial mass of isotope, measured in miligrams.
[tex]t[/tex] - Time, measured in years.
And time is cleared within the equation:
[tex]t = -\tau \cdot \ln \left[\frac{m(t)}{m_{o}} \right][/tex]
Then, time constant can be found as a function of half-life:
[tex]\tau = \frac{t_{1/2}}{\ln 2}[/tex] (Eq. 3)
If we know that [tex]t_{1/2} = 5730\,yr[/tex] and [tex]\frac{m(t)}{m_{o}} = 0.35[/tex], then:
[tex]\tau = \frac{5730\,yr}{\ln 2}[/tex]
[tex]\tau \approx 8266.643\,yr[/tex]
[tex]t = -(8266.643\,yr)\cdot \ln 0.35[/tex]
[tex]t \approx 8678.505\,yr[/tex]
The wood was cut approximately 8679 years ago.
Dale has three dollars more than twice the amount of money that Leo has.
Which statement makes this comparison using the correct variable expression?
A. If Leo has d dollars then Dale has 2(3) + D dollars.
B. If Leo has d dollars then Dale has 2d + 3 dollars.
C. If Leo has d dollars then Dale has d +2+3 dollars.
D. If Leo has d dollars then Dale has d/2 + 3 dollars.
Please help y'all I don't get this can you guys explain to?
Answer:
is leo has d dollars then dale has 2d + 3 dollars
Step-by-step explanation:
dale has twice the amount and three extra dollars.
so 2 x d is 2d
2d + 3
Write an equation in the line in slope intercept form
Answer:
Y=2x-1
Step-by-step explanation:
In order to find the slope, its rise over run. So you would move from (0,-1) to the next point it intercepts, (1,1) and find it from there
As for the Y-Intercept, it would just be wherever the line connects with the Y axis, which happens to be (0,-1) or Negative 1.
A circle is inscribed in a square. If the perimeter of the square is 40, what is the area of the circle? Use 3.14 for pi.
Answer:
78.5
Step-by-step explanation:
We have the perimeter of the square, which is 40, and 40/4=10. In this picture, we see that the circle's diameter is the same as the length of one side of the square. Therefore, the diameter of the circle is 10. The are formula for circles is [tex]\pi r^{2}[/tex], where [tex]r[/tex] is the radius. The radius of the circle is just the diameter divided by 2, and 10/2=5. Now, [tex]5^2[/tex] is 25, and [tex]3.14\cdot25=78.5[/tex].
7th grade math help me plzzzz
Answer:
a. -14
b. -13
c. -5
d. -3
e. -12
f. 0
Step-by-step explanation:
hope it helps
Answer:
A is -14.
B is -13
C is -5
D is -3
E is -12
F is 0
Step-by-step explanation:
A, B, E both numbers are negative so you just add them together and add a negative sign.
C would read 4-9
D 10-7 and add a - to the answer
F is 6-6
Find the slope of the line
SOMEONE PLEASE HELP ILL GIVE BRAINLIEST
Answer:
A.
Step-by-step explanation:
In a certain state's lottery, 45 balls numbered 1 through 45 are placed in a machine and eight of them are drawn at random. If the eight numbers drawn match the numbers that a player had chosen, the player wins $1,000,000. In this lottery, the order in which the numbers are drawn does not matter.
Compute the probability that you win the million-dollar prize if you purchase a single lottery ticket. Write your answer as a reduced fraction.
P
(win) =
A single lottery ticket costs $2. Compute the Expected Value, to the state, if 10,000 lottery tickets are sold. Round your answer to the nearest dollar.
Answer: $
A single lottery ticket costs $2. Compute the Expected Value, to you, if you purchase 10,000 lottery tickets. Round your answer to the nearest dollar.
Answer: $
Step-by-step explanation:
The order of the numbers doesn't matter, so we'll use combinations instead of permutations. The number of combinations is:
₄₅C₈ = 215,553,195
So the probability of a ticket having the winning combination is 1 / 215,553,195.
The expected value to the state is:
E(X) = 10,000 (1) ($2) + 10,000 (1 / 215,553,195) (-$1,000,000)
E(X) = $19954
The expected value to you is:
E(X) = 10,000 (1) (-$2) + 10,000 (1 / 215,553,195) ($1,000,000)
E(X) = -$19954
-4 (2x + 13) + 3x = 80
How do you solve this out and get the answer
Answer:
-132/5
Step-by-step explanation:
-4(2x+13) + 3x = 80
-8x - 52 + 3x = 80
-5x = 80+52
5x = -132
x = -132/5
Feel free to mark this as brainliest! :D
If b^2 = 25 then b= Answer it please
Answer:
b = 5
mark me as brainliest plz!! :DD
Which equation shows y=3x−15 in standard form?
A. 15x−5y=1
B. 15x+5y=−1
C. 5x−15y=1
D. 5x−15y=−1
Answer:
c 5x -15y =1
Step-by-step explanation:
5x-15y=1
-5x -15y= 1 -5x change the signs on both sides of the equation
15y = -1 +5x divide both sides by 15
y = -1/15 + 1/3 x Reorder the terms
y = 3x-15
:)
All options are wrong here.
Given equation is [tex]y=3x-15[/tex].
the equation given here is in form of [tex]y=mx+c[/tex] . The general equation of any straight line where m is the gradient of the line (how steep the line is) and c is the y -intercept (the point in which the line crosses the y -axis) .
We have to write [tex]y=3x-15 \\[/tex] in standard form.
The standard form for linear equations in two variables is Ax+By=C.
Now we convert [tex]y=3x-15[/tex] in standard form.
Here [tex]y=3x-15\\[/tex]
[tex]y-3x=-15\\\\-y+3x=15[/tex]
[tex]3x-y=15[/tex]
But no options match with the above standard form of equation.
Hence all options are wrong here.
For more details on standard form for linear equations follow the link:
https://brainly.com/question/7380540
I need help nowwwwww !!!!!????
you should just have to times the yards by three like the second one is 12
Help me with this question quick PLZz
Answer:7 to 3
Step-by-step explanation:
Answer:
3:10
Step-by-step explanation:
3 Parrots
Total Number of Birds: 3+7=10
Ellie bakes 12 muffins everyday since Monday. Jacob said that on Friday, she would be able to bake 72 muffins in total. Is Jacob right? Yes or no, explain. :)
QUICK
solve this equation
a^n+b^n=
Which expression is the coefficient of the n term -1
Answer:
C. -2n² - n + 5
Step-by-step explanation:
In expression C, the coefficient of the n term is -1;
The expression in choice C is given as:
-2n² - n + 5
The coefficient is the number before a variable;
For n², the coefficient is -2
for n, the coefficient is -1
30 point question! WILL AWARD BRAINLIEST!
A ball is thrown across a playing field from a height of h = 5 ft above the ground at an angle of 45° to the horizontal at the speed of 20 ft/s. It can be deduced from physical principles that the path of the ball is modeled by the function
y = − (32/(20^2))x2 + x + 5
Find the horizontal distance the ball has traveled when it hits the ground. (Round your answer to one decimal place.)
Answer:
Answers are down below ;)
Step-by-step explanation:
y = − (32/(20^2))x2 + x + 5
Plug into the calculator: -32/20^2 = -.08x^2
Find the maximum height attained by the ball:
Rewrite the equation:
y= -.08x^2 + x +5
This parabola is a negative meaning that it will be maximum
to find the maximum we use the formula -b/2a
-(1)/ 2 (-.08) = -1/ -.16= 6.25
we plug 6.25 back into the equation y= -.08(6.25)^2+ (6.25) +5 = 8.125
The maximum height attained by the ball: 8.125 feet
Find the horizontal distance the ball has traveled when it hits the ground.
This can be found with the quadratic equation, x = [-b ± √(b2-4ac)]/2a
a= -.08 , -b= -1, c= 5 (When you are plugging in the numbers, make sure to break them down).
-(-1)± √(-1)^2-4(-.08)(5)] 2(-.08) -->
[-1 ± √(1 + 1.28)]/-.16 = [-1 ± √(2.6)]/-.16 = [-1 ± 1.61]/-.16 =
The horizontal distance of the ball is x = 16.31 feet
Say thank you by commenting down below :)
What is the first step when solving the equation 3(3x-5x)+2=-8
Answer:
Collect the like terms
Step-by-step explanation:
(3x-5x)
3x (-2x) + 2 = -8
Number 10 plzz???????
If it takes 930 kg of food to feed a pair
of elephants for 3 days, how much food
would you need to feed them for a week?
Answer:
2170
Step-by-step explanation:
930 divided be 3= 310
310 multiplied by 7=2170
Everglades National Park is 225 mi long. What scale is needed to draw a map of Everglades National Park that is 10 in. long?
A. 1 in. = 22.5 mi
B. 10 in. = 225 mi
C. 1 in. = 0.04 mi
D. 10 in. = 22.5 mi
Answer:
A. 1 in. = 22.5 mi
Step-by-step explanation:
Since 22.5 x 10 = 225, we can conclude that this will fit the scale needed. B. is incorrect because it is simply illogical in context with a scale and the question. C. is incorrect since 10 x 0.04 is 0.4, which does not equal 10. D. is incorrect since we need the scale to add up to equal 225 mi, not 22.5.
Hope this helps!
18 feet above ground level and 7 feet below ground level
Answer:
11
Step-by-step explanation:
2
Divide: 4:- =
5
HELP FAST!!!!!!!!!
10/4 if its right also have a good my dude