Question

Mr. Tomas ereated a 2-foot wide garden path around a circular garden. The

radius of the garden is 7 feet. He wants to cover the path in stones. If Mr. Tomas
needs 1 bag of stones for every 6 square feet of path, how many bags of stones
will he need to cover his garden path?

Answer 1

Answer: 17 bags.

Explanation:

We can think of the area of the path, as the difference between the area of a circle with a radius of 9ft (the 7 ft of the circular garden plus the 2ft of the path) and the area of a circle with a radius of 7ft.

Remember that the area of a circle with radius R is:

R = pi*R^2

Where pi = 3.14

Then the area of the path will be:

A = 3.14*(9ft)^2 - 3.14*(7ft)^2 = 100.48 ft^2

Now, we know that Mr. Tomas needs 1 bag of stones for every 6 square feet of path.

Then let's see how many times we have 6ft^2 in the 100.48 ft^2 of the area, this is equal to the quotient between 100.48 ft^2 and 6ft^2

N = (100.48 ft^2)/( 6ft^2) = 16.75

This means that we will need 16.75 bags of stones, but we can not have a 0.75 of a bag, then we should round up our number to 17.

Then Mr. Tomas will need 17 bags of stones to cover his garden path.