Question

The average July rainfall in a city is 7 inches , but the actual rainfall may vary by as much as 4 inches. What is the range , in inches , of the possible rainfall in July?

A) 3 < R < 7
B) 7 < R < 11
C) 3 < R < 11
( ALL ARE INCLUSIVE I just didn't have the sign for it )

Answer 1

The answer is C. (too lazy to explain how sorry)

Answer 2

C.
`3\leq R\leq 11`

Explanation:

Let R represent range, in inches, of the possible rainfall in July.

We have been given that the average July rainfall in a city is 7 inches , but the actual rainfall may vary by as much as 4 inches.

We will use tolerance formula to solve our given problem.

`|\text{Actual}-\text{Ideal}|\leq\text{Tolerance}`

`|R-7|\leq4`

Using absolute value rule
`|u|\leq a`, then
`-a\leq u\leq a`, we will get:

`-4\leq R-7\leq4`

`-4+7\leq R-7+7\leq4+7`

`3\leq R\leq 11`

Therefore, option C represents range, in inches, of the possible rainfall in July.