(х+10)/370=20 900/(х+5)=100
(х+10)/370=20
x+10=20*370
x+10=7400
x=7400-10
x-7390
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(7390+10):370=20
7400:370=20
20=20
900/(х+5)=100
x+5 = 900:100
x+5 = 9
x=9 - 5
x= 4
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900:(4+5)=100
900 : 9 = 100