1. 1/7+7/8×5/7+37.5%
=1/7 +5/8 +3/8
=1/7 + 1
=1又7分之1
2. 8×5/16+40%÷4
=5/2 +0.4÷4
=2.5 +0.1
=2.6
3. 2/3+（4/7+50%）×7/25
=2/3 +(4/7 +1/2)×7/25
=2/3 +(15/14)×(7/25 )
=2/3 +3/10
=(20+9)/30
=29/30
4. (1+1/2）÷（1-50%）
=(3/2)÷(1/2)
=(3/2)×2
=3