math help

What is 88/15 + 7/10?

What is 88/15 + 7/10?

Let's add

88
15
+
7
10

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 88 by 10, and get 880, then we multiply 15 by 10 and get 150.

88/15 times 10

Do the same for the second term. We multiply 7 by 15, and get 105, then multiply 15 by 10 and get 150.

7/10 times 15

So now our fractions look like this:

880
150
+
105
150

Step 2

Since our denominators match, we can add the numerators.

880 + 105 = 985

So the answer is:

985
150

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...

Are both the numerator and the denominator evenly divisible by 5? Yes! So we reduce it:

985
150
÷ 5 =
197
30

Let's try dividing by that again...

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...

No good. 31 is larger than 30. So we're done reducing.

There you have it! Here's the final answer to 88/15 + 7/10

88
15
+
7
10
=
197
30
© 2014 Randy Tayler