(1)
1又6/7-6/7×5/6
=1+6/7-6/7×5/6
=1+6/7×1-6/7×5/6
=1+6/7×(1-5/6)
=1+6/7×1/6
=1+1/7
=1又1/7
(2)
9/5x3/7÷9/5×3/7
=9/5÷9/5x3/7×3/7
=1x3/7×3/7
=9/49
(1)
1又6/7-6/7×5/6
=1+6/7-6/7×5/6
=1+6/7×1-6/7×5/6
=1+6/7×(1-5/6)
=1+6/7×1/6
=1+1/7
=1又1/7
(2)
9/5x3/7÷9/5×3/7
=9/5÷9/5x3/7×3/7
=1x3/7×3/7
=9/49