Question

suppose that you have two square garden plots: One is 10’ x 10’ and the other is 15 x 15’. You want to cover both gardens with a 1 inch layer of mulch. If the 10 x 10 garden took 3 1/2 bags of mulch, could you calculate how many bags of mulch you need for the 15 x 15 garden by setting up the following proportion 3.5/10 = X/15. explain clearly why or why not. If the answer is no is there another proportion that you could set up? it may help you to make drawings of the Gardens

Answer 1

Explanation:

This question can be solved using a rule of three.

For each configuration, we need the perimeter and the amount of bags of mulch.

For a square of side s, the perimeter is P = 4s

If the 10 x 10 garden took 3 1/2 bags of mulch:

10x10 means that s = 10.

So the perimeter is:

P = 4*10 = 40

The number of bags of mulch is:

3 1/2 = 3 + (1/2) = 3 + 0.5 = 3.5

15 x 15 garden

15x15 means that s = 15.

The perimeter is: P = 4*s = 4*15 = 60.

The number of bags is X.

Now applying the rule of three:

With the number of bags and the perimeter.

3.5 bags - 40'

X bags - 60'

Now we apply cross multiplication: