用递等式计算,能简算的要用简便方法计算.84.67-(24.67+15.3)1.25×3.2 1 4 + 3 4 ÷ 1 4 + 3 4 1 5 ÷13+ 4 5 × 1 13 .
(1)84.67-(24.67+15.3), =84.67-24.67-15.3, =(84.67-24.67)-15.3, =60-15.3, =44.7; (2)1.25×3.2, =1.25×8×0.4, =(1.25×8)×0.4, =10×0.4, =4; (3)
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=1+3, =4; (4)
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