Mathematics problems in grade one of junior high school (solving equations and calculating) (1) To solve the equation: 150x/(1-60%)=150(x+20)/(1-15%) (2) Calculation: 48+20-[12000*(1-20%)/150] [Note: solving equations and calculating need to write process]

(1) Solution equation: 150x / (1-60%) = 150 (x + 20) / (1-15%)
150x/0.4=150(x+20)/0.85
x/40=(x+20)/85
85x=40(x+20)
85x=40x+800
35x=800
x=800/35
x=160/7
(2) Calculation: 48 + 20 - [12000 * (1-20%) / 150]
=68-[12000*0.2/150]
=68-80*0.2
=68-16
=52

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