math help

What is 64/16 - 7/9?

What is 64/16 - 7/9?

Here's how to subtract 7/9 from 64/16:

64
16
7
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 64 by 9, and get 576.

Then we multiply 7 by 16, and get 112.

Next we give both terms new denominators -- 16 × 9 = 144.

So now our fractions look like this:

576
144
112
144

Step 2

Since our denominators match, we can subtract the numerators.

576 − 112 = 464

So the answer is:

464
144

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:

464
144
÷ 2 =
232
72

Let's try dividing by 2 again...

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

232
72
÷ 2 =
116
36

Let's try dividing by 2 again...

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

116
36
÷ 2 =
58
18

Let's try dividing by 2 again...

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

58
18
÷ 2 =
29
9

Let's try dividing by 2 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...

No good. 11 is larger than 9. So we're done reducing.

There you have it! The final answer is:
64
16
7
9
=
29
9