How can I rewrite the sentence more clear?

Question

I have a sentence. I want to rewrite it is more clear. Could you help me to correct it? I am not family of English. Thank you in advance Explanation: I considered three methods: method A, B and C to measure the weight of each box. I want to measure which one is best method. To fair comparison among methods, the number of books in each box has to same. For example, if I have 8 books in box1. I will use method A to measure the weight of box1. Then I need to use same amount of book (8 books) to measure the weight using method B. The bellow sentence describer what I said. However, it is not clear to understand. Could you help me to correct it? >To fair comparison among methods, the amount of book in each box of referenced method is same with amount of book in compared method.

Answer 1

Based on your description, I hope this is what you intended:

"To obtain a fair comparison, the number of books in the box is the same in each of the three methods."