2.4%*[40-X]=4%*[40-X]如何算
问题描述:
2.4%*[40-X]=4%*[40-X]如何算
答
设 40-X = k
2.4% k = 4% k
=> k = 0
=> 40 - X =0
X = 40
遇到这题就要用逻辑啦~:P