两道简算题,急用!(1/4+5/8)/(7/4-7/8)(3/5-1/4)/(3/4+1/5)

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两道简算题,急用!(1/4+5/8)/(7/4-7/8)(3/5-1/4)/(3/4+1/5)
两道简算题,急用!
(1/4+5/8)/(7/4-7/8)
(3/5-1/4)/(3/4+1/5)

两道简算题,急用!(1/4+5/8)/(7/4-7/8)(3/5-1/4)/(3/4+1/5)
1. (1/4+5/8)/(7/4-7/8)
=7/8 / 7/4 - 7/8 / 7/8
=7/8 * 4/7 - 7/8 * 8/7
=1/2 - 1
=-0.5
2.简算我也不会,答案是7/19.

用分配率算第一题得49/64第二题得133/20

1
7/19

1
19/20