math help

What is 55/55 + 5/7?

What is 55/55 + 5/7?

This is how we add

55
55
+
5
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 55 by 7, and get 385, then we multiply 55 by 7 and get 385.

55/55 times 7

Do the same for the second term. We multiply 5 by 55, and get 275, then multiply 55 by 7 and get 385.

5/7 times 55

The problem now has new fractions to add:

385
385
+
275
385

Step 2

Since our denominators match, we can add the numerators.

385 + 275 = 660

This yields the answer

660
385

Step 3

The last step is to reduce the fraction if we can.

To find out, we try dividing it by 2...

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:

660
385
÷ 5 =
132
77

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...

Are both the numerator and the denominator evenly divisible by 11? Yes! So we reduce it:

132
77
÷ 11 =
12
7

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

No good. 11 is larger than 7. So we're done reducing.

And we're done! Here's the final answer to 55/55 + 5/7

55
55
+
5
7
=
12
7
© 2014 Randy Tayler