The text book explains the word "productivity" as following :
the amount of work that a person, company, etc. does compared with how much time, money, and effort it takes them.
Here I cannot understand the part "it takes them"
I am familiar with the verb 'take'. For example
'It takes the tragedy of Tom's death for us to meet here'
which is a slight modification of sentence in some script.
I think the following is correct.
how much time, money and effort it takes for them to do
How would you say about my opinion ?