计算下面各题,能简算的要简算,并写出主要的计算过程.①7.8﹣8.75+2.2﹣1.25 ②13.2÷(9.4﹣5)+5.32③1﹣﹣④﹣(+) ⑤+(﹣)
3÷8═= ÷24= %= :56.
3:4= :8=9: == %
3÷ == :12=七成五= %
÷10==9: == :40.
18: = :20== ÷40=1.2.