甲數的五分之二比乙數的二分之一少5,已知乙數為20,求甲數
設甲數為x.
1/2*20-2/5x=5
解得,x=12.5
3.2×0.25×0.125(簡便計算)
3.2×0.25×0.125
=0.4×0.25×8×0.125
=0.1×1
=0.1
3.2×0.25×0.125(簡便計算)(寫出過程)
3.2×0.25×0.125
=0.4×0.25×8×0.125
=0.1×1
=0.1
25+125*3.2簡便運算
25+125*3+125*0.2=25+375+25=425
不曉得够簡便不
簡便運算:【5-3又7/8÷(1又5/6+2.25×1/3)】÷0.125
【5-3又7/8÷(1又5/6+2.25×1/3)】÷0.125
=【5-3又7/8÷(11/6+9/4×1/3)】÷1/8
=【5-31/8÷(11/6+9/4×1/3)】×8
=【5-31/8÷(11/6+3/4)】×8
=【5-31/8÷(31/12)】×8
=【5-3/2】×8
=40-12
=28
39.7×2.8+3.97×72脫式計算題答案
39.7×2.8+3.97×72
=3.97×10×2.8+3.97×72
=3.97×28+3.97×72
=3.97×(28+72)
=3.97×100
=397
72×39+72怎樣簡便運算?
要用梯等式!
72×39+72
=72x(39+1)
=72x40
=2880
39*8+6*39-39-4簡便計算
39*8+6*39-39-4
=39×(8+6-1)-4
=39×13-4
=503
45乘45+55乘45怎樣用遞等式簡便計算
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55乘45减45乘45用遞等式簡便計算果斷採納
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