Question

A 100 rupee note was changed to 10 and 5 rupee notes, 15 notes in all. How many of each notes?​

Answer 1

Total number of notes is 11. Value is 100 rupees

5x + 20y = 100 and x + y = 11 are the two equations.

We can simplify…

5x + 20 y - 5x - 5y = 100 - 55 = 45

15y = 45 so y = 3

x = 11 - y = 8

Answer 2

Total number of notes is 11.

Explanation:

Value is 100 rupees…

5x + 20y = 100 and x + y = 11 are the two equations.

We can simplify…

5x + 20 y - 5x - 5y = 100 - 55 = 45

15y = 45 so y = 3

x = 11 - y = 8

So, we have 8 notes of 5 rupees denomination and 3 notes of 20 rupees denomination.

I hope it helps you.