math help

What is 2/4 + 3/5?

What is 2/4 + 3/5?

Here's how to add

2
4
+
3
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 2 by 5, and get 10, then we multiply 4 by 5 and get 20.

2/4 times 5

Do the same for the second term. We multiply 3 by 4, and get 12, then multiply 4 by 5 and get 20.

3/5 times 4

The problem now has new fractions to add:

10
20
+
12
20

Step 2

Since our denominators match, we can add the numerators.

10 + 12 = 22

The sum we get is

22
20

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:

22
20
÷ 2 =
11
10

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. So next you try the next prime number, which is 11...

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

And we're done! Here's the final answer to 2/4 + 3/5

2
4
+
3
5
=
11
10
© 2014 Randy Tayler