Question

1、从7/9的倒数里减去从7分之9的倒数里减去7分之6除以5分之6的商,差是多少?

Answer 1

=9/7减去7/9减去5/7

=4/7减去7/9

=36/63减去49/63

=-13/63

或

=9/7-（9/7-6/7）/6/5

=9/7-3/7*5/6

=9/7-5/21

=27/21-5/21

=22/21

=1又1/21

（X-15%X)*5/34=1/8

85%X*5/34=1/8

85%X=17/20

85X=85

X=1