math help

What is 100/50 + 3/11?

What is 100/50 + 3/11?

This is how we add

100
50
+
3
11

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 100 by 11, and get 1100, then we multiply 50 by 11 and get 550.

100/50 times 11

Do the same for the second term. We multiply 3 by 50, and get 150, then multiply 50 by 11 and get 550.

3/11 times 50

So now our fractions look like this:

1100
550
+
150
550

Step 2

Since our denominators match, we can add the numerators.

1100 + 150 = 1250

Now we have an answer.

1250
550

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:

1250
550
÷ 2 =
625
275

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...

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

625
275
÷ 5 =
125
55

So far so good... let's try to divide by that number again.

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

125
55
÷ 5 =
25
11

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 7...

No good. So next you try the next prime number, which is 11...

No good. So next you try the next prime number, which is 13...

No good. 13 is larger than 11. So we're done reducing.

And we're done! Here's the final answer to 100/50 + 3/11

100
50
+
3
11
=
25
11
© 2014 Randy Tayler