# Math Help - Unable to Solve Problem

1. ## Unable to Solve Problem

Question: How many decorative bricks 10 inches long would be needed to go around a circular garden that is 8 feet in diameter? Use Pi = 3.14

This is what I did
Step 1: I read the problem and decided that it is asking me to find the perimiter. I used the formula pi x d. The answer I got was 25.12. How did the author get 30? Am I doing something wrong? I have spent over an hour trying to figure it out.

2. Originally Posted by kidari
Question: How many decorative bricks 10 inches long would be needed to go around a circular garden that is 8 feet in diameter? Use Pi = 3.14

This is what I did
Step 1: I read the problem and decided that it is asking me to find the perimiter. I used the formula pi x d. The answer I got was 25.12. How did the author get 30? Am I doing something wrong? I have spent over an hour trying to figure it out.
8ft = 48in

So the circumference is

$C = \pi D$

$= 3.14 \times 48\,\textrm{in}$

$= 150.72\,\textrm{in}$.

So i would say you would need about 16 x 10in bricks...

Are you sure the question didn't say 8ft in radius? Because then you would need about 30... (32 in fact...)

3. Thank you =)