Question

A lady has only 25paise and1 rupee coins in her purse. If in all she has 70 coins totaling Rs.40,how many coins of each type has she? Solve it.

Answer 1

40 coins of 25 paise will 10 rupee
30 coinse of 1 rupee will 30 rupee

70 coinse 40 rupee

Answer 2

Let total number of 25 paise coins be x and 1 rupee or 100 paise coins be y.
So total number of coins = x+y= 70 ...(1)
Value of the x coins will be 25x paise
Value of the y coins will be 100x paise
So total value = 25x + 100y = 40 rupees = 4000 paise...(2)
Multiply (1) by 25 to cancel out the x terms
25x + 100y = 4000
- 25x + 25y = 1750
75y = 2250
So y = 30
By substituting y = 30 in (1) you will get x = 40
So, there are 30 coins of value 1 rupee and 40 coins of value 25 paise.