math help

What is 9/60 + 2/7?

What is 9/60 + 2/7?

Let's add

9
60
+
2
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 9 by 7, and get 63, then we multiply 60 by 7 and get 420.

9/60 times 7

Do the same for the second term. We multiply 2 by 60, and get 120, then multiply 60 by 7 and get 420.

2/7 times 60

The problem now has new fractions to add:

63
420
+
120
420

Step 2

Since our denominators match, we can add the numerators.

63 + 120 = 183

The sum we get is

183
420

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:

183
420
÷ 3 =
61
140

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...

No good. 67 is larger than 61. So we're done reducing.

There you have it! Here's the final answer to 9/60 + 2/7

9
60
+
2
7
=
61
140
© 2014 Randy Tayler