Question

in how many ways can we give change for 100 rupees using 1 rupee and 2 rupee coins

Answer 1

100/2 = 50
100/1 = 100
so, 100+50 = 150 ways to give change

hope
it
helps

Answer 2

We have to convert Rs 100 in denomination of Rs 1 coin and Rs 2 coin.

It can be written in the form of equation as

→ 100 = x + 2 y, where x is Rs 1 coin and y is Rs 2 coin.

Start from , x=0, we get y = 100, So one ordered pair is (0,100),

Similarly (2,49), (4,48),..............(98,1),(100,0).

So , there are ,0, 2,4,6.8,...........100.→ 51 ways in which Rs 100 can be changed into Rs 1 and Rs 2 coins.