Question

70 coins of 10 paise and 50 paise are mixed in a purse if total value of money in purse is equal to 19 find the number of each type of coins

Answer 1

Suppose the number of 50 paise coins are x.
Total number of coins = 70
Then number of 10 paise coins = (70 - x)
So total money = $0.50x+0.10\left(70-x\right)=19$
$$\begin{gathered} \Rightarrow 0.50x+7-0.10x=19 \\ \Rightarrow 0.40x=12 \\ \Rightarrow x=\frac{12}{0.40}=30 \end{gathered}$$
so number of 50 paise coins = 30
And number of 10 paise coins = 70 - 30 = 40