1.(1-5/6×3/5)÷4
=(1-1/2)÷4
=1/2÷4
=1/8
2.(2/3+4/5)÷1/15
=2/3÷1/15+4/5÷1/15
=10+12
=22
3.5/6×3/5+4/7+3/7
=(5/6×3/5)+(4/7+3/7)
=1/2+1
=3/2
4.(3/4-1/8)÷2
=5/8÷2
=5/16
5.128×(5/8-3/8)
=128×1/4
=32