math help

What is 91/6 + 4/7?

What is 91/6 + 4/7?

This is how we add

91
6
+
4
7

Step 1

We can't add two fractions with different denominators (the bottom number). So you need to get a common denominator - both bottom numbers need to match. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator.

So we multiply 91 by 7, and get 637, then we multiply 6 by 7 and get 42.

91/6 times 7

Do the same for the second term. We multiply 4 by 6, and get 24, then multiply 6 by 7 and get 42.

4/7 times 6

So now our fractions look like this:

637
42
+
24
42

Step 2

Since our denominators match, we can add the numerators.

637 + 24 = 661

Now we have an answer.

661
42

Step 3

Last of all, we need to simplify the fraction, if possible. Can it be reduced to a simpler fraction?

To find out, we try dividing it by 2...

Nope! So now we try the next greatest prime number, 3...

Nope! So now we try the next greatest prime number, 5...

Nope! So now we try the next greatest prime number, 7...

Nope! So now we try the next greatest prime number, 11...

Nope! So now we try the next greatest prime number, 13...

Nope! So now we try the next greatest prime number, 17...

Nope! So now we try the next greatest prime number, 19...

Nope! So now we try the next greatest prime number, 23...

Nope! So now we try the next greatest prime number, 29...

Nope! So now we try the next greatest prime number, 31...

Nope! So now we try the next greatest prime number, 37...

Nope! So now we try the next greatest prime number, 41...

Nope! So now we try the next greatest prime number, 43...

No good. 43 is larger than 42. So we're done reducing.

There you have it! Here's the final answer to 91/6 + 4/7

91
6
+
4
7
=
661
42
© 2014 Randy Tayler