In a mega store, ⁷₉ of the customers were female. There were 90 more female customers. Within five minutes, some female customers left the mega store. As a result, there were ³₇ as many male customers as female customers. How many female customers left the mega store during the five minutes?
Number of female customers = 7 u
Total number of customers = 9 u

Number of male customers
= 9 u - 7 u
= 2 u

7 u - 2 u = 90
5 u = 90

1 u = 90 ÷ 5 = 18

Number of female customers at first
= 7 u
= 7 x 18
= 126

Number of male customers
= 2 u
= 2 x 18
= 36

The number of male customers remains unchanged.
3 p = 36

1 p = 36 ÷ 3 = 12

New number of female customers
= 7 p
= 7 x 12
= 84

Number of female customers who left
= 126 - 84
= 42

Answer(s): 42