作业帮126-?÷25×28.7＝12.5求问号数字.如题.
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126-?÷25×28.7＝12.5求问号数字.如题.
126-?÷25×28.7＝12.5求问号数字.
如题.
126-?÷25×28.7＝12.5求问号数字.如题.
先乘除,后加减
126 - A ÷ 25 × 28.7 ＝ 12.5
126 - (A ÷ 25 × 28.7) = 12.5 [先乘除,刮起来成为一体]
126 - 12.5 = (A ÷ 25) × 28.7 [等式左右互换,加变减,乘变除]
113.5 = (A ÷ 25) × 28.7
113.5 ÷ 28.7 = A ÷ 25
113.5 / 28.7 = A / 25
(113.5 x 25) / 28.7 = A
A = 28375/287 = 98又 249/287 = 98.86759581881533
?=(126-12.5)÷28.7×25=98.8675958
（126-12.5）×25/28.7
？ = (126-12.5)÷28.7×25=98.8675958188153
？ = (126-12.5)÷28.7×25
先乘除，后加减
126 - A ÷ 25 × 28.7 ＝ 12.5
126 - (A ÷ 25 × 28.7) = 12.5 [先乘除，刮起来成为一体]
126 - 12.5 = (A ÷ 25) × 28.7 [等式左右互换，加变减，乘变除]
113.5 = (A ÷ 25) × 28.7
113.5 ÷ 28.7 = A ÷ 25
113....
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先乘除，后加减
126 - A ÷ 25 × 28.7 ＝ 12.5
126 - (A ÷ 25 × 28.7) = 12.5 [先乘除，刮起来成为一体]
126 - 12.5 = (A ÷ 25) × 28.7 [等式左右互换，加变减，乘变除]
113.5 = (A ÷ 25) × 28.7
113.5 ÷ 28.7 = A ÷ 25
113.5 / 28.7 = A / 25
(113.5 x 25) / 28.7 = A
A = 28375/287 = 98又 249/287 = 98.86759581881533
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