Question

A sum of 500 rupees in the from of denominations of 5 rupees and 10 rupees. If the total number of notes is 90 find the number of notes of each type.

Answer 1

let x be denomination in terms of 5 ₹

and, y be in terms of 10 ₹

therefore given, 5x+10y=500--------(1)

also given x+y= 90 -------(2)

multiply eq.2 by 10

10x+10y=900------(3)

substract eq.1 and 3

x= 80

y= 10

therefore there are 80 5₹ note and 10 10₹ note