In a wholesale centre, ⁵₇ of the customers were male. There were 63 more male customers. Within five minutes, some male customers left the wholesale centre. As a result, there were ⁷₉ as many female customers as male customers. How many male customers left the wholesale centre during the five minutes?
Number of male customers = 5 u
Total number of customers = 7 u

Number of female customers
= 7 u - 5 u
= 2 u

5 u - 2 u = 63
3 u = 63

1 u = 63 ÷ 3 = 21

Number of male customers at first
= 5 u
= 5 x 21
= 105

Number of female customers
= 2 u
= 2 x 21
= 42

The number of female customers remains unchanged.
7 p = 42

1 p = 42 ÷ 7 = 6

New number of male customers
= 9 p
= 9 x 6
= 54

Number of male customers who left
= 105 - 54
= 51

Answer(s): 51