math help

What is 64/16 + 1/5?

What is 64/16 + 1/5?

This is how you add

64
16
+
1
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 64 by 5, and get 320, then we multiply 16 by 5 and get 80.

64/16 times 5

Do the same for the second term. We multiply 1 by 16, and get 16, then multiply 16 by 5 and get 80.

1/5 times 16

The problem now has new fractions to add:

320
80
+
16
80

Step 2

Since our denominators match, we can add the numerators.

320 + 16 = 336

The sum we get is

336
80

Step 3

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

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

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

336
80
÷ 2 =
168
40

So far so good... let's try to divide by that number again.

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

168
40
÷ 2 =
84
20

So far so good... let's try to divide by that number again.

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

84
20
÷ 2 =
42
10

So far so good... let's try to divide by that number again.

Are both the numerator and the denominator evenly divisible by 2? Yes! So we reduce it:

42
10
÷ 2 =
21
5

So far so good... let's try to divide by that number again.

No good. So next you try the next prime number, which is 3...

No good. So next you try the next prime number, which is 5...

No good. So next you try the next prime number, which is 7...

No good. 7 is larger than 5. So we're done reducing.

And we're done! Here's the final answer to 64/16 + 1/5

64
16
+
1
5
=
21
5
© 2014 Randy Tayler