math help

What is 4/52 + 7/9?

What is 4/52 + 7/9?

This is how you add

4
52
+
7
9

Step 1

We can't add two fractions with different denominators (the bottom number). So you need to get a common denominator - both bottom numbers need to match. To do this, you'll multiply the denominators times each other... but the numerators have to change, too. They get multiplied by the other term's denominator.

So we multiply 4 by 9, and get 36, then we multiply 52 by 9 and get 468.

4/52 times 9

Do the same for the second term. We multiply 7 by 52, and get 364, then multiply 52 by 9 and get 468.

7/9 times 52

So now our fractions look like this:

36
468
+
364
468

Step 2

Since our denominators match, we can add the numerators.

36 + 364 = 400

So the answer is:

400
468

Step 3

Last of all, we need to simplify the fraction, if possible. Can it be reduced to a simpler fraction?

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:

400
468
÷ 2 =
200
234

Let's try dividing by that again...

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

200
234
÷ 2 =
100
117

Let's try dividing by that again...

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

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...

Nope! So now we try the next greatest prime number, 83...

Nope! So now we try the next greatest prime number, 89...

Nope! So now we try the next greatest prime number, 97...

Nope! So now we try the next greatest prime number, 101...

No good. 101 is larger than 100. So we're done reducing.

There you have it! Here's the final answer to 4/52 + 7/9

4
52
+
7
9
=
100
117
© 2014 Randy Tayler