Jessica would like to make a small notebook from A4 paper. She cut it into 4 and then sew the pieces together. If she has 40 sheets of A4 paper, how thick is the notebook?

Answer 1

Answer is 320 Pls answer with working out & method

Answer 2

4 small sheets for each piece of paper
4*40 = 160 sheets
2 pages per sheet, right?

Answer 3

So is 160 the answer because i might be wrong