陳向東數學第三章第26題 解答不是很懂

amber4cdream

A certain company has found that the number c laber hours required to produce x items is directly proportional to the square root of x. if 3 labor hours are required to produce 20 items. How many labor hours are required to produce 40 items?


这题解答说
c 和x的函数关系是 c = k * sqrt(x);


请问k是哪里来的呢？


谢谢～

wilz

It comes from the word "proportional".

amber4cdream

Thank you for your help!