Question

12分之7减(8分之3加6分之1) 5分之4加4分之1减20分之19 1又15分之2加5分之3减1 请用简便算法算出来

Answer 1

7/12-(3/8+1/6)

=7/12-(9/24+4/24)

=14/24-13/24

=1/24

4/5+1/4-19/20

=16/20+5/20-19/20

=2/20.

=1/10

1又2/15+3/5-1

=1+2/15+3/5-1

=2/15+3/5

=2/15+9/15

=11/15