Correct Answer: 124
Explanation:
Therefore 0.20 x x + 0.25 (324 - x) = 71 ⟺ 20x + 25 (324 - x) = 7100
⟺ 5x= 1000 ⟺ x = 200. Hence, number of 25-paise coins = (324 - x) - 124.