Honors problem

Question

A retailer gave his costumers 1 7/8 dollars in change,which he afterwards found, was 4/5 of a dollar too much: What was the exact amount of change due?

Answer 1

Let the change due be x then

 

x = 15 / 8 - 4 / 5

 

= ( 75 - 32 ) / 40

 

= 43 / 40

 

= 1 3/40