math help

What is 87/100 - 6/9?

What is 87/100 - 6/9?

Here's how to subtract 6/9 from 87/100:

87
100
 −
6
9

Step 1

We can't subtract two fractions with different denominators. So you need to get a common denominator. 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 87 by 9, and get 783.

Then we multiply 6 by 100, and get 600.

Next we give both terms new denominators -- 100 × 9 = 900.

So now our fractions look like this:

783
900
 −
600
900

Step 2

Since our denominators match, we can subtract the numerators.

783 − 600 = 183

So the answer is:

183
900

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...

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
900
 ÷ 3 =
61
300

Let's try dividing by 3 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! The final answer is:
87
100
 −
6
9
 =
61
300

6/9 + 1/2
6/9 - 1/2
6/9 + 1/3
6/9 - 1/3
6/9 + 2/3
6/9 - 2/3
6/9 + 1/4
6/9 - 1/4
6/9 + 2/4
6/9 - 2/4
6/9 + 3/4
6/9 - 3/4
6/9 + 1/5
6/9 - 1/5
6/9 + 2/5
6/9 - 2/5
6/9 + 3/5
6/9 - 3/5
6/9 + 4/5
6/9 - 4/5
6/9 + 1/6
6/9 - 1/6
6/9 + 2/6
6/9 - 2/6
6/9 + 3/6
6/9 - 3/6
6/9 + 4/6
6/9 - 4/6
6/9 + 5/6
6/9 - 5/6
6/9 + 1/7
6/9 - 1/7
6/9 + 2/7
6/9 - 2/7
6/9 + 3/7
6/9 - 3/7
6/9 + 4/7
6/9 - 4/7
6/9 + 5/7
6/9 - 5/7
6/9 + 6/7
6/9 - 6/7
6/9 + 1/8
6/9 - 1/8
6/9 + 2/8
6/9 - 2/8
6/9 + 3/8
6/9 - 3/8
6/9 + 4/8
6/9 - 4/8
6/9 + 5/8
6/9 - 5/8
6/9 + 6/8
6/9 - 6/8
6/9 + 7/8
6/9 - 7/8
6/9 + 1/9
6/9 - 1/9
6/9 + 2/9
6/9 - 2/9
6/9 + 3/9
6/9 - 3/9
6/9 + 4/9
6/9 - 4/9
6/9 + 5/9
6/9 - 5/9
6/9 + 6/9
6/9 - 6/9
6/9 + 7/9
6/9 - 7/9
6/9 + 8/9
6/9 - 8/9
6/9 + 1/10
6/9 - 1/10
6/9 + 2/10
6/9 - 2/10
6/9 + 3/10
6/9 - 3/10
6/9 + 4/10
6/9 - 4/10
6/9 + 5/10
6/9 - 5/10
6/9 + 6/10
6/9 - 6/10
6/9 + 7/10
6/9 - 7/10
6/9 + 8/10
6/9 - 8/10
6/9 + 9/10
6/9 - 9/10
6/9 + 1/11
6/9 - 1/11
6/9 + 2/11
6/9 - 2/11
6/9 + 3/11
6/9 - 3/11
6/9 + 4/11
6/9 - 4/11
6/9 + 5/11
6/9 - 5/11
6/9 + 6/11
6/9 - 6/11
6/9 + 7/11
6/9 - 7/11
6/9 + 8/11
6/9 - 8/11
6/9 + 9/11
6/9 - 9/11
6/9 + 10/11
6/9 - 10/11
6/9 + 1/12
6/9 - 1/12
6/9 + 2/12
6/9 - 2/12
6/9 + 3/12
6/9 - 3/12
6/9 + 4/12
6/9 - 4/12
6/9 + 5/12
6/9 - 5/12
6/9 + 6/12
6/9 - 6/12
6/9 + 7/12
6/9 - 7/12
6/9 + 8/12
6/9 - 8/12
6/9 + 9/12
6/9 - 9/12
6/9 + 10/12
6/9 - 10/12
6/9 + 11/12
6/9 - 11/12