Find each percent change. State if it is an increase or decrease.

9) From 16.6 to 13 i really need thi preferably have a good explanation so i can do it myself next time

21.69% decrease.

Step-by-step explanation:

We want to determine the percent change from 16.6 to 13.

First, since 13 is smaller than 16.6, we know that this is decrease.

Percent change is given by the formula:

The new value is 13 and the old value is 16.6. Substitute:

Evaluate:

Use a calculator:

We ignore the negative because the negative simply tells us that it's decreasing. (Likewise, if the answer's positive, it's an increase.)

In conclusion, the percent change is an approximate 21.69% decrease.

walter needs to make at least 5 more cookies but no more than 40. 5 ≤ x ≤ 40

step-by-step explanation:

20 ≤ x + 15 ≤ 55

subtract 15 from all parts

20-15 ≤ x + 15-15 ≤ 55-15

5 ≤ x ≤ 40

this means how many more cookies he has to make

walter needs to make at least 5 more cookies, but no more than 40 cookies; 5 ≤ x ≤ 40

7.3

step-by-step explanation: