math help

What is 78/92 + 4/8?

What is 78/92 + 4/8?

Here's how to add

78
92
+
4
8

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 78 by 8, and get 624, then we multiply 92 by 8 and get 736.

78/92 times 8

Do the same for the second term. We multiply 4 by 92, and get 368, then multiply 92 by 8 and get 736.

4/8 times 92

The problem now has new fractions to add:

624
736
+
368
736

Step 2

Since our denominators match, we can add the numerators.

624 + 368 = 992

The sum we get is

992
736

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:

992
736
÷ 2 =
496
368

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:

496
368
÷ 2 =
248
184

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:

248
184
÷ 2 =
124
92

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:

124
92
÷ 2 =
62
46

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:

62
46
÷ 2 =
31
23

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. 29 is larger than 23. So we're done reducing.

And we're done! Here's the final answer to 78/92 + 4/8

78
92
+
4
8
=
31
23
© 2014 Randy Tayler