24×（6分之5＋8分之1）
=24×5/6+24×1/8
=20+3
=23
（1/7＋4/5＋12/35）×7/9
=1/7×7/9+4/5×7/9+12/35×7/9
=1/9+28/45+4/15
=5/45+28/45+12/45
=45/45
=1
3×1/4×1/6
=3×1/6×1/4
=1/2×1/4
=1/8
5分之2×15×10分之1
=2/5×15×1/10
=6×1/10
=3/5