Question

The weight of male Americans between the ages of 18 and 25 is normally distributed, with a mean of 160.4 lb and a standard deviation of 27 lb. One definition of obesity states that a person is obese if the z-score of his or her weight is greater than 2. What is the obesity threshold weight for a young adult American male? Round your answer to the nearest tenth. A. 200.9 lb B. 187.4 lb C. 173.9 lb D. 214.4 lb

Answer 1

you need to substitute.... then do: 160.4(mean)+2(x)*27(z)= 214.4lb

Answer 2

Explanation:

We know that
`z=\frac{x-{\mu}}{\sigma}` (1)

and also we are given that a person is obese if the z-score of his or her weight is greater than 2.

Thus, using this information we can rewrite the above equation (1),

`2\geq(x-160.4)/(27)`

Solving this equation, we have

⇒
`54\geq(x-160.4)`

⇒
`54+160.4\geq x`

⇒
`214.4\geq x`

Thus, the obesity threshold weight for a young adult American male is
`214.4lb\geq x`.