Question

the sum of rupees 500 is in the form of notes of denomination of rupees 5 and rupees 10 if the total number of notes is 90 find the number of notes of each type

Answer 1

let 5 rupee note be x= x×5
therefore 10 rupee note will be equal to=(90-x)10
x×5+(90-x)10=500
5x+900-10x=500
-5x+900=500
-5x=500-900
-5x=-400
x=-400÷-5
x=80
and (90-x)=(90-80)=10
therefore 5 rupee note=80 and 10 rupee note=10