1.(x+100)/240－x/280≥0.6 2.(1-5%)x≥1.5
问题描述：
1.(x+100)/240－x/280≥0.6 2.(1-5%)x≥1.5
答
1,240与280最小公倍数是1680,所以两边同时乘以1680得
7（X+100）-6X≥1008
7X+700-6X≥1008
X≥308
2,0.95X≥1.5
X≥30/19