math help

What is 9/60 + 1/7?

What is 9/60 + 1/7?

Here's how to add

9
60
+
1
7

Step 1

We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator.

Now we multiply 9 by 7, and get 63, then we multiply 60 by 7 and get 420.

9/60 times 7

Now for the second term. You multiply 1 by 60, and get 60, then multiply 60 by 7 and get 420.

1/7 times 60

This gives us a new problem that looks like so:

63
420
+
60
420

Step 2

Since our denominators match, we can add the numerators.

63 + 60 = 123

So what's the answer so far?

123
420

Step 3

Can this fraction be reduced?

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:

123
420
÷ 3 =
41
140

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. So next you try the next prime number, which is 23...

No good. So next you try the next prime number, which is 29...

No good. So next you try the next prime number, which is 31...

No good. So next you try the next prime number, which is 37...

No good. So next you try the next prime number, which is 41...

No good. So next you try the next prime number, which is 43...

No good. 43 is larger than 41. So we're done reducing.

And we're done! Here's the final answer to 9/60 + 1/7

9
60
+
1
7
=
41
140
© 2014 Randy Tayler