math help

What is 72/63 + 4/11?

What is 72/63 + 4/11?

This is how we add

72
63
+
4
11

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 72 by 11, and get 792, then we multiply 63 by 11 and get 693.

72/63 times 11

Do the same for the second term. We multiply 4 by 63, and get 252, then multiply 63 by 11 and get 693.

4/11 times 63

The problem now has new fractions to add:

792
693
+
252
693

Step 2

Since our denominators match, we can add the numerators.

792 + 252 = 1044

The sum we get is

1044
693

Step 3

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

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

Nope! So now we try the next greatest prime number, 3...

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

1044
693
÷ 3 =
348
231

Let's try dividing by that again...

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

348
231
÷ 3 =
116
77

Let's try dividing by that again...

Nope! So now we try the next greatest prime number, 5...

Nope! So now we try the next greatest prime number, 7...

Nope! So now we try the next greatest prime number, 11...

Nope! So now we try the next greatest prime number, 13...

Nope! So now we try the next greatest prime number, 17...

Nope! So now we try the next greatest prime number, 19...

Nope! So now we try the next greatest prime number, 23...

Nope! So now we try the next greatest prime number, 29...

Nope! So now we try the next greatest prime number, 31...

Nope! So now we try the next greatest prime number, 37...

Nope! So now we try the next greatest prime number, 41...

Nope! So now we try the next greatest prime number, 43...

Nope! So now we try the next greatest prime number, 47...

Nope! So now we try the next greatest prime number, 53...

Nope! So now we try the next greatest prime number, 59...

Nope! So now we try the next greatest prime number, 61...

Nope! So now we try the next greatest prime number, 67...

Nope! So now we try the next greatest prime number, 71...

Nope! So now we try the next greatest prime number, 73...

Nope! So now we try the next greatest prime number, 79...

No good. 79 is larger than 77. So we're done reducing.

There you have it! Here's the final answer to 72/63 + 4/11

72
63
+
4
11
=
116
77
© 2014 Randy Tayler