math help

What is 9/16 + 4/5?

What is 9/16 + 4/5?

This is how to add

9
16
+
4
5

Step 1

Of course, you can't add two fractions if the denominators (bottom numbers) don't match. To get a common denominator, multiply the denominators together. Then we fix the numerators by multiplying each one by their other term's denominator.

Now you multiply 9 by 5, and get 45, then we multiply 16 by 5 and get 80.

9/16 times 5

Do the same for the second term. We multiply 4 by 16, and get 64, then multiply 16 by 5 and get 80.

4/5 times 16

The problem now has new fractions to add:

45
80
+
64
80

Step 2

Since our denominators match, we can add the numerators.

45 + 64 = 109

This yields the answer

109
80

Step 3

The last step is to reduce the fraction if we can.

To find out, we try dividing 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...

Nope. Try the next prime number, 83...

No good. 83 is larger than 80. So we're done reducing.

Congratulations! Here's your final answer to 9/16 + 4/5

9
16
+
4
5
=
109
80
© 2014 Randy Tayler