math help

What is 78/92 + 3/12?

What is 78/92 + 3/12?

This is how we add

78
92
+
3
12

Step 1

We still have different denominators (bottom numbers), though, so we need to get a common denominator. This will make the bottom numbers match. Multiply the denominators together first. Now, multiply each numerator by the other term's denominator.

Now we multiply 78 by 12, and get 936, then we multiply 92 by 12 and get 1104.

78/92 times 12

Now for the second term. You multiply 3 by 92, and get 276, then multiply 92 by 12 and get 1104.

3/12 times 92

This gives us a new problem that looks like so:

936
1104
+
276
1104

Step 2

Since our denominators match, we can add the numerators.

936 + 276 = 1212

That gives us an answer of

1212
1104

Step 3

Can this fraction be reduced?

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

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

1212
1104
÷ 2 =
606
552

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:

606
552
÷ 2 =
303
276

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...

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

303
276
÷ 3 =
101
92

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 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. So next you try the next prime number, which is 47...

No good. So next you try the next prime number, which is 53...

No good. So next you try the next prime number, which is 59...

No good. So next you try the next prime number, which is 61...

No good. So next you try the next prime number, which is 67...

No good. So next you try the next prime number, which is 71...

No good. So next you try the next prime number, which is 73...

No good. So next you try the next prime number, which is 79...

No good. So next you try the next prime number, which is 83...

No good. So next you try the next prime number, which is 89...

No good. So next you try the next prime number, which is 97...

No good. 97 is larger than 92. So we're done reducing.

And we're done! Here's the final answer to 78/92 + 3/12

78
92
+
3
12
=
101
92
© 2014 Randy Tayler