Answer: 20
Step-by-step explanation:
We assume that the heights of boys in a high school basketball tournament are normally distributed.
Given : Mean height of boys : 
inches.
Standard deviation: 
inches.
Let x denotes the heights of boys in a high school basketball tournament .
Then the probability that a boy is taller than 70 inches will be :-
![P(x> 70)=1-P(x\leq70)\\\\=1-P(\dfrac{x-\mu}{\sigma}\leq\dfrac{70-70}{2.5})\\\\=1-P(z\leq0)=1-0.5=0.5\ \ \text{[by using z-value table]}](https://tex.z-dn.net/?f=P%28x%3E%2070%29%3D1-P%28x%5Cleq70%29%5C%5C%5C%5C%3D1-P%28%5Cdfrac%7Bx-%5Cmu%7D%7B%5Csigma%7D%5Cleq%5Cdfrac%7B70-70%7D%7B2.5%7D%29%5C%5C%5C%5C%3D1-P%28z%5Cleq0%29%3D1-0.5%3D0.5%5C%20%5C%20%5Ctext%7B%5Bby%20using%20z-value%20table%5D%7D)
Now, the expected number of boys in a group of 40 who are taller than 70 inches will be :-
Hence, the expected number of boys in a group of 40 who are taller than 70 inches=20
20x+3
This shouldddd be the answer sorry if I’m wrong, but if you group all the x variables together they add up to twenty, then you just add “+3” being that it has no x and therefore must be put in some form of separate group!
I am pretty sure that B is the answer
Answer:
x = 9.5
Step-by-step explanation:
Given
= 
( cross- multiply )
3(4x - 6) = 4(2x + 5) ← distribute parenthesis on both sides
12x - 18 = 8x + 20 ( subtract 8x from both sides )
4x - 18 = 20 ( add 18 to both sides )
4x = 38 ( divide both sides by 4 )
x = 
= 9.5
The length would be 22 ft.
The width would be 7 ft.
A=lw
A=22(7)
A=154 ft^2
