Question

(7/11+8/15)-(7/11-7/15)脱式计算

Answer 1

(7/11+8/15)-(7/11-7/15)

=7/11+8/15-7/11+7/15

=7/11-7/11+8/15+7/15

=(7/11-7/11)+(8/15+7/15)

=0+1

=1

7/30+3/8+23/30-4/8

=7/30+23/30 +3/8-4/8

=1-1/8

=7/8