Question

10 friends went for a dinner. The bill amounted to ₹2700. Some of them gave ₹300 towards the bill and some gave ₹200. How many gave ₹200.

Answer 1

So,

Let us assume that x persons gave 200 rupee notes and y persons gave 300 rupee notes

Now,

There were in together 10 friends so,

x + y =10..................1)

Also if we equate the amount spend on 200 and 300 rupee notes then

200x +300y = 2700........................2)

Multiplying equation 1) by 200 and then substracting by 2) we get

300y - 200y = 2700 - 2000

100y= 700

y=7

Substituting y=7 in equation 1) we get,

x + 7= 10

x=3

So,

3 person spent 200 rupee notes and 7 spend 300 rupee notes