math help

What is 64/4 + 7/10?

What is 64/4 + 7/10?

Let's add

64
4
+
7
10

Step 1

We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator.

Now we multiply 64 by 10, and get 640, then we multiply 4 by 10 and get 40.

64/4 times 10

Now for the second term. You multiply 7 by 4, and get 28, then multiply 4 by 10 and get 40.

7/10 times 4

This gives us a new problem that looks like so:

640
40
+
28
40

Step 2

Since our denominators match, we can add the numerators.

640 + 28 = 668

So what's the answer so far?

668
40

Step 3

Can this fraction be reduced?

First, we attempt to divide it by 2...

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

668
40
÷ 2 =
334
20

Now, try the same number again.

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

334
20
÷ 2 =
167
10

Now, try the same number again.

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...

No good. 11 is larger than 10. So we're done reducing.

Congratulations! Here's your final answer to 64/4 + 7/10

64
4
+
7
10
=
167
10
© 2014 Randy Tayler