Question

3/8×（7/8+1/6）÷3/4 9/10×（5/6-2/5）÷13/25

1＋3又1/6+5又1/12+7又1/20+9又1/30+11又1/42

Answer 1

3/8×(7/8+1/6)÷3/4
=3/8×(1/8+1/6)×4/3
=1/2×(1/8+1/6)
=1/2×(3/24+4/24)
=1/2×7/24
=7/48

9/10×(5/6-2/5)÷13/25
=9/10×(25/30-12/30)
=9/10×13/30×25/13
=9/10×25/30
=9/10×5/6
=3/4

1＋3又1/6+5又1/12+7又1/20+9又1/30+11又1/42
=1+3+1/6+5+1/12+7+1/20+9+1/30+11+1/42
=(1+3+5+7+9+11)+(1/6+1/12+1/20+1/30+1/42)
=12*3+[(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+(1/5-1/6)+(1/6-1/7)]
=36+(1/2-1/7)
=36+(7/14-2/14)
=36+5/14
=36又5/14