math help

What is 64/4 + 8/10?

What is 64/4 + 8/10?

This is how you add

64
4
+
8
10

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 10, and get 640, then we multiply 4 by 10 and get 40.

64/4 times 10

Do the same for the second term. We multiply 8 by 4, and get 32, then multiply 4 by 10 and get 40.

8/10 times 4

The problem now has new fractions to add:

640
40
+
32
40

Step 2

Since our denominators match, we can add the numerators.

640 + 32 = 672

The sum we get is

672
40

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:

672
40
÷ 2 =
336
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:

336
20
÷ 2 =
168
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:

168
10
÷ 2 =
84
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 64/4 + 8/10

64
4
+
8
10
=
84
5
© 2014 Randy Tayler