- Thread starter Satya
- Start date

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

http://www.mathwizz.com/fractions/help/help4.htm

S

http://www.mathwizz.com/fractions/help/help4.htm

Wow, that is neat!

Long Division. It's easier than you think.

I suck at long division.

Without a calculator, is there a faster way to reduce fractions than by factoring?

Factoring really isn't that bad. You just have to know the trick for 2, 3, 4, and 5. You'll rarely need anything higher.

http://www.mathwizz.com/fractions/help/help4.htm

Wow, Euclidean Algorithm! I completely forgot about that! Great find!

Factoring really isn't that bad. You just have to know the trick for 2, 3, 4, and 5. You'll rarely need anything higher

There's a trick?

Even numbers can be factored by two.

If you add both digits together and that number is divisible by three, then the original number is divisible by three (63 --> 6+3=9 --> 63 is divisible by three)

I forget the rule to four, but that's okay cuz I never check for four anyways.

If the number ends in a 5 or 0, it is divisible by five.

If a number is divisible by both two and three, then it is divisible by six.

Even numbers can be factored by two.

If you add both digits together and that number is divisible by three, then the original number is divisible by three (63 --> 6+3=9 --> 63 is divisible by three)

I forget the rule to four, but that's okay cuz I never check for four anyways.

If the number ends in a 5 or 0, it is divisible by five.

If a number is divisible by both two and three, then it is divisible by six.

Wow, I did not know the tricks for the second and last one. It feels like my elementary education was seriously lacking in the math department. I wonder what the trick for 4 is.

There is a pattern with four, like all the other numbers, that's not too hard to figure out:

4, 8, 12, 16, 20 || 24, 28, 32, 36, 40...

ends in: 4, 8, 2, 6, 0 || 4, 8, 2, 6, 0...

So if it's divisible by four, it would end in one of those numbers, in increments of 20