math help

What is 70/51 - 3/7?

What is 70/51 - 3/7?

Here's how to subtract 3/7 from 70/51:

70
51
3
7

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 70 by 7, and get 490.

Then we multiply 3 by 51, and get 153.

Next we give both terms new denominators -- 51 × 7 = 357.

So now our fractions look like this:

490
357
153
357

Step 2

Since our denominators match, we can subtract the numerators.

490 − 153 = 337

So the answer is:

337
357

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...

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...

Nope! So now we try the next greatest prime number, 103...

Nope! So now we try the next greatest prime number, 107...

Nope! So now we try the next greatest prime number, 109...

Nope! So now we try the next greatest prime number, 113...

Nope! So now we try the next greatest prime number, 127...

Nope! So now we try the next greatest prime number, 131...

Nope! So now we try the next greatest prime number, 137...

Nope! So now we try the next greatest prime number, 139...

Nope! So now we try the next greatest prime number, 149...

Nope! So now we try the next greatest prime number, 151...

Nope! So now we try the next greatest prime number, 157...

Nope! So now we try the next greatest prime number, 163...

Nope! So now we try the next greatest prime number, 167...

Nope! So now we try the next greatest prime number, 173...

Nope! So now we try the next greatest prime number, 179...

Nope! So now we try the next greatest prime number, 181...

Nope! So now we try the next greatest prime number, 191...

Nope! So now we try the next greatest prime number, 193...

Nope! So now we try the next greatest prime number, 197...

Nope! So now we try the next greatest prime number, 199...

Nope! So now we try the next greatest prime number, 211...

Nope! So now we try the next greatest prime number, 223...

Nope! So now we try the next greatest prime number, 227...

Nope! So now we try the next greatest prime number, 229...

Nope! So now we try the next greatest prime number, 233...

Nope! So now we try the next greatest prime number, 239...

Nope! So now we try the next greatest prime number, 241...

Nope! So now we try the next greatest prime number, 251...

Nope! So now we try the next greatest prime number, 257...

Nope! So now we try the next greatest prime number, 263...

Nope! So now we try the next greatest prime number, 269...

Nope! So now we try the next greatest prime number, 271...

Nope! So now we try the next greatest prime number, 277...

Nope! So now we try the next greatest prime number, 281...

Nope! So now we try the next greatest prime number, 283...

Nope! So now we try the next greatest prime number, 293...

Nope! So now we try the next greatest prime number, 307...

Nope! So now we try the next greatest prime number, 311...

Nope! So now we try the next greatest prime number, 313...

Nope! So now we try the next greatest prime number, 317...

Nope! So now we try the next greatest prime number, 331...

Nope! So now we try the next greatest prime number, 337...

Nope! So now we try the next greatest prime number, 347...

No good. 347 is larger than 337. So we're done reducing.

There you have it! The final answer is:
70
51
3
7
=
337
357