(2/3+4/15×5/8)÷2/3
=(2/3+4/15×5/8)×3/2
=2/3×3/2+4/15×5/8×3/2
=1+1/2
=1又1/2
(5/7÷8+1/8)×16=5/7×1/8×16+1/8×16
=10/7+2
=3又3/7
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(2/3+4/15×5/8)÷2/3
=(2/3+1/6)*3/2
=5/6*3/2
=5/4
=1.25
(5/7÷8+1/8)×16
=(5/7+1)/8 *16
=2*12/7
=3又3/7