Question

I need help with these two problems !!

Answer 1

Not so sure about the second one, but the first one is pretty simple:

The area of a circle = pi x radius^2

Since you need to find the area of the entire dvd, I'm assuming they mean if the hole in the center wasn't there, so add that to the diameter.

12+1.5 = 13.5

Half of the diameter is the radius, so half of 13.5 = 6.75

Now, multiply pi (3.14) by the radius, but have the radius squared. You'd write the equation like this:

3.14 x 6.75^2 (or on paper, the ^2 would be a small two diagonal from the 5)

Actual answer: 143.06625

You can round that to 143.