math help

What is 4/10 + 3/5?

What is 4/10 + 3/5?

Let's add

4
10
+
3
5

Step 1

Our denominators (bottom numbers) don't match, so we can't add yet.

Since 5 is evenly divided by 10, we can multiply just one term to get a common denominator.

Multiply 3 by 2, and get 6, then we multiply 5 by 2 and get 10.

3/5 times 2

The problem now has new fractions to add:

4
10
+
6
10

Step 2

Since our denominators match, we can add the numerators.

4 + 6 = 10

The sum we get is

10
10

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:

10
10
÷ 2 =
5
5

Now, try the same number again.

Nope. Try the next prime number, 3...

Nope. Try the next prime number, 5...

Are both the numerator and the denominator evenly divisible by 5? Yes! So we reduce it:

5
5
÷ 5 =
1
1

Now, try the same number again.

No good. 5 is larger than 1. So we're done reducing.

Congratulations! Here's your final answer to 4/10 + 3/5

4
10
+
3
5
=
1
1
= 1
© 2014 Randy Tayler