math help

What is 100/24 + 3/7?

What is 100/24 + 3/7?

Let's add

100
24
+
3
7

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 100 by 7, and get 700, then we multiply 24 by 7 and get 168.

100/24 times 7

Do the same for the second term. We multiply 3 by 24, and get 72, then multiply 24 by 7 and get 168.

3/7 times 24

The problem now has new fractions to add:

700
168
+
72
168

Step 2

Since our denominators match, we can add the numerators.

700 + 72 = 772

The sum we get is

772
168

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:

772
168
÷ 2 =
386
84

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

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

386
84
÷ 2 =
193
42

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. So next you try the next prime number, which is 13...

No good. So next you try the next prime number, which is 17...

No good. So next you try the next prime number, which is 19...

No good. So next you try the next prime number, which is 23...

No good. So next you try the next prime number, which is 29...

No good. So next you try the next prime number, which is 31...

No good. So next you try the next prime number, which is 37...

No good. So next you try the next prime number, which is 41...

No good. So next you try the next prime number, which is 43...

No good. 43 is larger than 42. So we're done reducing.

And we're done! Here's the final answer to 100/24 + 3/7

100
24
+
3
7
=
193
42
© 2014 Randy Tayler