1、(3/4+7/8+1/12)x24
=3/4x24+7/8x24+1/12x24
=18+21+2
=41
2、(2/3+5/7x7/24)÷7/8
=2/3x8/7+5/7x7/24x8/7
=16/21+5/21
=1