math help

What is 64/16 + 2/10?

What is 64/16 + 2/10?

Let's add

64
16
+
2
10

Step 1

We can't add two fractions with different denominators (the bottom number). So you need to get a common denominator - both bottom numbers need to match. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator.

So we multiply 64 by 10, and get 640, then we multiply 16 by 10 and get 160.

64/16 times 10

Do the same for the second term. We multiply 2 by 16, and get 32, then multiply 16 by 10 and get 160.

2/10 times 16

So now our fractions look like this:

640
160
+
32
160

Step 2

Since our denominators match, we can add the numerators.

640 + 32 = 672

Now we have an answer.

672
160

Step 3

Last of all, we need to simplify the fraction, if possible. Can it be reduced to a simpler fraction?

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
160
÷ 2 =
336
80

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
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 + 2/10

64
16
+
2
10
=
21
5
© 2014 Randy Tayler