Mr. scott counted 85 customers in his store the first day it was open, and 170 customers the second day. what was the percent of increase in customers? a. 10% b. 50% c. 85% d. 100%

D. 100%

Step-by-step explanation:

percent change = (new number - old number)/(old number) * 100%

The new number is the second day's number, 170, and the old number is the first day's number, 85.

percent change = (170 - 85)/(85) * 100%

percent change = 85/85 * 100%

percent change = 1 * 100%

percent change = 100%

Since the percent change is a positive number, it is a percent increase.

The percent increase was 100%.

D. 100%

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!