math help

What is 30/50 + 3/8?

What is 30/50 + 3/8?

Here's how to add

30
50
+
3
8

Step 1

Can you add yet? Nope! The denominators don't match. We need a common denominator. So next we take both denominators and multiply them. Next, take each numerator and multiply it by the denominator of the other term.

So, we multiply 30 by 8, and get 240, then we multiply 50 by 8 and get 400.

30/50 times 8

Now for the second term. You multiply 3 by 50, and get 150, then multiply 50 by 8 and get 400.

3/8 times 50

We now have a new problem, that looks like this:

240
400
+
150
400

Step 2

Since our denominators match, we can add the numerators.

240 + 150 = 390

Answer:

390
400

Step 3

Now, do we need to simplify this fraction?

First, we attempt to divide it by 2...

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

390
400
÷ 2 =
195
200

Now, try the same number again.

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

Nope. Try the next prime number, 5...

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

195
200
÷ 5 =
39
40

Now, try the same number again.

Nope. Try the next prime number, 7...

Nope. Try the next prime number, 11...

Nope. Try the next prime number, 13...

Nope. Try the next prime number, 17...

Nope. Try the next prime number, 19...

Nope. Try the next prime number, 23...

Nope. Try the next prime number, 29...

Nope. Try the next prime number, 31...

Nope. Try the next prime number, 37...

Nope. Try the next prime number, 41...

No good. 41 is larger than 39. So we're done reducing.

Congratulations! Here's your final answer to 30/50 + 3/8

30
50
+
3
8
=
39
40
© 2014 Randy Tayler