81÷14+17×1/14
=1/14×(81+17)
=1/14×98
=7
(5/12+1/9)×72
=5/12×72+1/9×72
=30+8
=38
68÷【0.5×(7.5-0.7)】
=68÷【0.5×6.8】
=68÷6.8÷0.5
=10÷0.5
=20
81÷14+17×1/14
=1/14×(81+17)
=1/14×98
=7
(5/12+1/9)×72
=5/12×72+1/9×72
=30+8
=38
68÷【0.5×(7.5-0.7)】
=68÷【0.5×6.8】
=68÷6.8÷0.5
=10÷0.5
=20