Question

計算． 5 7 × 2 3 =	2 11 × 3 5 =	7 12 × 3 4 =	6 7 × 2 15 =
3 10 × 5 8 =	24 35 × 5 12 =	15 52 × 13 25 =	7 18 × 9 14 =

Answer 1

分析：計算分數乘法時，把因數的分母和分子交叉約分后再乘．

解答：

解： 5 7 × 2 3 = 10 21	2 11 × 3 5 = 6 55	7 12 × 3 4 = 7 16	6 7 × 2 15 = 4 35
3 10 × 5 8 = 3 16	24 35 × 5 12 = 2 7	15 52 × 13 25 = 3 20	7 18 × 9 14 = 1 4

點評：此題考查分數乘法的計算方法．