math help

What is 15/60 + 3/4?

What is 15/60 + 3/4?

Here's how you add

15
60
+
3
4

Step 1

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

Since 4 is evenly divided by 60, we can multiply just one term to get a common denominator.

Multiply 3 by 15, and get 45, then we multiply 4 by 15 and get 60.

3/4 times 15

The problem now has new fractions to add:

15
60
+
45
60

Step 2

Since our denominators match, we can add the numerators.

15 + 45 = 60

This yields the answer

60
60

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:

60
60
÷ 2 =
30
30

Now, try the same number again.

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

30
30
÷ 2 =
15
15

Now, try the same number again.

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

Are both the numerator and the denominator evenly divisible by 3? Yes! So we reduce it:

15
15
÷ 3 =
5
5

Now, try the same number again.

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 15/60 + 3/4

15
60
+
3
4
=
1
1
= 1
© 2014 Randy Tayler