Question

2 dozens of flowers make 5 centerpieces how many dozens does it take to make 20 centerpieces

Answer 1

1 dozen= 12, so if 2 dozen makes 5 center pieces or 24=5 then you have to divide 20 by 5 to get 4.
2x4= 8

Answer 2

it takes 8 dozens of flour.

5x4=20 so the person needs 4 times more than 2 dozens. 2x4=8 therefor, the person needs 8 dozens of flour.