Question

A lady went to bank with rs 100000 and asked the cashier to give her rs 500 & 1000 currency notes in return , she got 175 currency notes in all .find the number of each kind of currency notes

Answer 1

Let 500 notes X

And  

1000notes =Y

Then first equation is

X+y=175

And second equation is

500x+1000Y=100000

500(X+2Y)=100000

X+2Y=200

THEN USE ELEMINATION METHOD

ANSWER COME

X=150

Y=25