original: 25 new: 18

Question

what is the percent in change?

 

and for original: 36      new: 45

Answer 1

If a quantity changed from 25 down to 18, the change is -7 and that represents a decrease (thus the -) of 28% because 7/25 = (4/4)(7/28) = 28/100.

 

Now you can figure the other one: from 36 up to 45 is an increase of ____ which is a ratio ____:36 = _____%.

Note that the basis of comparison is (original) 36.

Answer 2

The basic logic says:  "What percent of 25 is 18?"

18 = (x/100)25

x = 1800/25

x = 72%

18 is 72% of 25

This is a decrease of 28% from the original number

0r a change of -28%

 

Follow the same logic with a change from 36 to 45

45 = (x/100)36

When you solve for x it will be greater than 100.

Subtract the original 100% from it to get the

POSITIVE change in percentage.