问题 解答题

求为知数x.

(1)16.5-x=10.5

(2)0.37÷x=0.74

(3)x+3×0.7=6.5.

答案

(1)16.5-x=10.5,

16.5-x+x=10.5+x,

10.5+x-10.5=16.5-10.5,

x=6;

(2)0.37÷x=0.74,

0.37÷x×x=0.74×x,

0.74×x÷0.74=0.37÷0.74,

x=0.5;

(3)x+3×0.7=6.5,

x+2.1=6.5,

x+2.1-2.1=6.5-2.1,

x=4.4.

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