math help

What is 45/3 + 2/10?

What is 45/3 + 2/10?

Here's how we add

45
3
+
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 45 by 10, and get 450, then we multiply 3 by 10 and get 30.

45/3 times 10

Do the same for the second term. We multiply 2 by 3, and get 6, then multiply 3 by 10 and get 30.

2/10 times 3

So now our fractions look like this:

450
30
+
6
30

Step 2

Since our denominators match, we can add the numerators.

450 + 6 = 456

Now we have an answer.

456
30

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:

456
30
÷ 2 =
228
15

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 3...

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

228
15
÷ 3 =
76
5

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 5...

Nope! So now we try the next greatest prime number, 7...

No good. 7 is larger than 5. So we're done reducing.

There you have it! Here's the final answer to 45/3 + 2/10

45
3
+
2
10
=
76
5
© 2014 Randy Tayler