math help

What is 7/16 + 2/5?

What is 7/16 + 2/5?

This is how you add

7
16
+
2
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 7 by 5, and get 35, then we multiply 16 by 5 and get 80.

7/16 times 5

Do the same for the second term. We multiply 2 by 16, and get 32, then multiply 16 by 5 and get 80.

2/5 times 16

The problem now has new fractions to add:

35
80
+
32
80

Step 2

Since our denominators match, we can add the numerators.

35 + 32 = 67

The sum we get is

67
80

Step 3

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

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...

Nope! So now we try the next greatest prime number, 47...

Nope! So now we try the next greatest prime number, 53...

Nope! So now we try the next greatest prime number, 59...

Nope! So now we try the next greatest prime number, 61...

Nope! So now we try the next greatest prime number, 67...

Nope! So now we try the next greatest prime number, 71...

No good. 71 is larger than 67. So we're done reducing.

There you have it! Here's the final answer to 7/16 + 2/5

7
16
+
2
5
=
67
80
© 2014 Randy Tayler