Question

Ms sharp baked 21 rays of cookies with 35 cookies on each tray if she needs to bake 840 cookies how many more trays will she need to make

Answer 1

35/21 = 840/x

simplify

5/3 = 840/x

multiply 5 and x, 840 and 3

5x = 2,520

divide each side by 5 to get x alone

x = 540 trays