# It All Adds Up- June 12, 2016

Hello and welcome to the first ‘It All Adds Up’ post of  the summer!

For my It All Adds Up posts, I will be posting a new math problem every Sunday, and releasing the answers the following Saturday. On Sundays, I will create a new post (like this one), along with updating my It All Adds Up page, which can be found here. The following Saturday, I will update only my It All Adds Up page, with the correct answers to the math problem.

### To start the summer off, here is this week’s current math problem:

One subject that I studied in the late months of school was finding the area of a circle to find the volume of different shapes (such as a cone, cylinder, sphere). In order to find the volume of these shapes, though, we first need to find the area of a circle, which is the base of each of these objects. This is the standard formula for finding the AREA of a circle:

# a=πr²

To find the area, we substitute for the pi symbol (in this case, we’ll use 3.14), and you substitute for the radius (r) which is halfway across the middle of the circle. Take a look at this diagram:

As you can see, our circle has a radius of 7cm. In the first step, we substitute pi for 3.14 and 7 squared for r. In the second step, we find the value of 7 squared (49). In the third step, we multiply both numbers together and add the unit and square the product.

Now that you know how to find the area of a circle, you’ll soon be able to find the volume of a cylinder. But first, for this week’s problem, use the formula to find the area of this circle:

Visit the It All Adds Up page on June 18 (this Saturday) for the correct answer to this problem, and look for a new post on June 19 (this Sunday).