A has 50 coins of 10 paise denominations. While B has 10 coins of 50 paise denominations. C has 20 coins of 25 paise denominations while D has 25 coins of 20 paise denominations. The average number of paise per person is :

Explanation:-

$$\eqalign{ & \frac{{\left[ {\left( {10 \times 50} \right) + \left( {50 \times 10} \right) + \left( {20 \times 25} \right) + \left( {25 \times 20} \right)} \right]}}{4} \cr & = 500\,{\text{paise}} \cr}$$