Question

Rekha has some notes of denomination rupees 10 and Sem notes of denomination rupees 20 which amount to rupees 190.If the number of the notes of denomination rupees 10 and the notes of denomination rupees 20 are interchanged,the total amount is rupees 230.Find the number of notes of denomination rupees 10 and that of rupess 20 separately in the beginning.

let the number of notes of denomination rupees 10 be 'x'
and Rupees 20 be 'y'

answer it fast and right...i will mark u as brainiest​

Answer 1

10x+20y=190---i

20x+10y=230---ii

Add i and ii and subtract i and ii

10x+20y+20x+10y=190+230⇒x+y=14

20x+10y-(10x+20y)=230-190⇒x-y=4

On solving these two equations we get x=9 and y=5