问题 解答题

求未知数X.

1717+X=2809X×72=729660÷X=420.

答案

(1)1717+X=2809,

1717+X-1717=2809-1717,

x=1092;

(2)X×72=72,

X×72÷72=72÷72,

x=1;

(3)9660÷X=420,

9660÷X×x=420×x,

9660÷420=420x÷420,

x=23.

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