解方程X-30%-(1-30%)X×五分之二=42
问题描述：
解方程X-30%-(1-30%)X×五分之二=42
答
x - 30% - (1 - 30%)x × 2/5 = 42
x - 0.3 - 0.7x × 0.4 = 42
x - 0.28x = 42 + 0.3
0.72x = 42.3
x = 42.3 ÷ 0.72
x = 58.75
答
由x-30%-（1-30%）x×（2/5）=42
x-0.3-0.7x×0.4=42
x-0.3-0.28x=42
0.72x=42+0.3
0.72x=42.3
x=42.3÷0.72
x=58.75.
答
X-30%-0.28X=42
X-0.28X=42+30%
0.72X=42.3
X=58.75