math help

What is 15/11 + 4/7?

What is 15/11 + 4/7?

This is how you add

15
11
+
4
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 15 by 7, and get 105, then we multiply 11 by 7 and get 77.

15/11 times 7

Now for the second term. You multiply 4 by 11, and get 44, then multiply 11 by 7 and get 77.

4/7 times 11

This gives us a new problem that looks like so:

105
77
+
44
77

Step 2

Since our denominators match, we can add the numerators.

105 + 44 = 149

So what's the answer so far?

149
77

Step 3

Can this fraction be reduced?

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

Nope. Try the next prime number, 3...

Nope. Try the next prime number, 5...

Nope. Try the next prime number, 7...

Nope. Try the next prime number, 11...

Nope. Try the next prime number, 13...

Nope. Try the next prime number, 17...

Nope. Try the next prime number, 19...

Nope. Try the next prime number, 23...

Nope. Try the next prime number, 29...

Nope. Try the next prime number, 31...

Nope. Try the next prime number, 37...

Nope. Try the next prime number, 41...

Nope. Try the next prime number, 43...

Nope. Try the next prime number, 47...

Nope. Try the next prime number, 53...

Nope. Try the next prime number, 59...

Nope. Try the next prime number, 61...

Nope. Try the next prime number, 67...

Nope. Try the next prime number, 71...

Nope. Try the next prime number, 73...

Nope. Try the next prime number, 79...

No good. 79 is larger than 77. So we're done reducing.

Congratulations! Here's your final answer to 15/11 + 4/7

15
11
+
4
7
=
149
77
© 2014 Randy Tayler