Answer:
b. The values X and Y are independent therefore, the mean is 34 seconds and the standard deviation is 50 seconds
Step-by-step explanation:
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Before the training, the mean running time for the students to run a mile was 402 seconds with standard deviation 40 seconds.
This means that 
After completing the program, the mean running time for the students to run a mile was 368 seconds with standard deviation 30 seconds.
This means that 
Which of the following is true about the distribution of X-Y?
They are independent, so:
This means that the correct answer is given by option b.
There is 75% decrease.
Step-by-step explanation:
Given,
Old value = 688 qt
New value = 172 qt
Change = New value - Old value
Change = 172 - 688
Change = -516 qt
The negative sign indicates decrease.
Decrease percent = 
Decrease percent = 
Decrease percent = 
Decrease percent = 75%
There is 75% decrease.
Keywords: division, subtraction
Learn more about subtraction at:
#LearnwithBrainly
Let me set an example to help solve this, say the poster is 100 inches by 90 inches. the length of the poster is reduced by 12% so subtract 12 from 100 to get you new length of 78 inches. the width is increased by 15% so multiply 90 by 15% to get 13.5 inches and add the to the 90 inches you have to get your new width of 103.5 inches. multiply them together to get your new area then divide the new area by the old area, subtract that number by 1 and multiply it by -1.
IN Δ MLN:
∠M = 18.3 , ∠L = 98.6 AND ∠N = 180 - (∠M + ∠L) = 180 - (18.3 + 98.6 ) = 63.1
IN Δ FGH:
∠F = 98.6 , ∠G = 61.1 AND ∠H = 180 - (∠F + ∠G ) = 180 - (98.6 + 61.1 ) = 20.3
∴ ONLY ∠N = ∠F = 98.6
There is no other <span>congruent </span>angles
So, The correct statement is :
Inaccurate. The triangles are not similar because angle M is not congruent to angle H, and angle N is not congruent to angle G.
Hi there!
PART A:
The system of equations we would use would be:
x + y = 22 (amount of items)
3x + 1y = 30 (cost)
Variables:
x = the amount of strawberry wafers bought at the price of $3
y = the amount of chocolate wafers bought at the price of $1
PART B:
To solve, we'll use substitution because we can easily isolate a variable using the first equation.
Work:
x + y = 22 (first equation)
y = 22 - x (isolating a variable)
3x + 1y = 30 (second equation)
3x + (22 - x) = 30 (substituting into the second equation)
2x + 22 = 30 (simplifying)
2x = 8 (subtracting)
x = 4 strawberry wafers
4 + y = 22 (substituting x into the first equation to solve for y)
y = 18 chocolate wafers
ANSWER:
They bought 4 strawberry wafers and 18 chocolate wafers.
Hope this helps!! :)
If there's anything else that I can help you with, please let me know!
