math help

What is 15/60 + 3/5?

What is 15/60 + 3/5?

This is how to add

15
60
+
3
5

Step 1

We have to make sure the denominators are equal.

60 goes into 5 evenly, so we only need to multiply one term to get a common denominator.

Multiply 3 by 12, and get 36, then we multiply 5 by 12 and get 60.

3/5 times 12

We now have a new problem, that looks like this:

15
60
+
36
60

Step 2

Since our denominators match, we can add the numerators.

15 + 36 = 51

Answer:

51
60

Step 3

Now, do we need to simplify this fraction?

First, we attempt to divide it by 2...

No good. So next you try the next prime number, which is 3...

Are both the numerator and the denominator evenly divisible by 3? Yes! So we reduce it:

51
60
÷ 3 =
17
20

So far so good... let's try to divide by that number again.

No good. So next you try the next prime number, which is 5...

No good. So next you try the next prime number, which is 7...

No good. So next you try the next prime number, which is 11...

No good. So next you try the next prime number, which is 13...

No good. So next you try the next prime number, which is 17...

No good. So next you try the next prime number, which is 19...

No good. 19 is larger than 17. So we're done reducing.

And we're done! Here's the final answer to 15/60 + 3/5

15
60
+
3
5
=
17
20
© 2014 Randy Tayler