Subtract mixed fraction from mixed fraction?

Answer 1

Mixed fractions, and fractions in general, aren't very hard to deal with.

A mixed fraction has a whole number in front, and a fraction next to it.

ex: 4 and (5/8ths)

Let's try to add 4 and (5/8ths) + 8 and (3/8ths).

What would you do if there were no fraction? ie: 4 + 8

You'd just add the numbers, right?

We do the same thing with mixed fractions, you can deal with the fractional parts after.

4 + 8 = 12.

But we still have to add (5/8) + (3/8).

To add fractions together, make sure they have the same bottom number.

Luckily 5/8 and 3/8 have a "common denominator", or same bottom number.

So all we have to do is add the tops together.

5+3 = 8.

and then put our sum over the common denominator. or 8/8.

and we know that 8/8ths is the same as 1 whole. (a whole number!)

We can add this to our original sum --> 4 + 8 + 1 = 13

4 and 5/8 + 8 and 3/8 = 13 ( and 0/8)

Try this one:

1 and 1/3 + 2 and 1/3

1) Add your whole numbers together....

2) Check to see if your fractions have the same bottom number. If they do, just add the top numbers and put the sum over the bottom number from both fractions.

Note, sometimes the denominators of the fractions are not the same! (eww)

ex: 5 and 1/5 + 4 and 8/15

We need to make the denominators of both fractions the same

Let's look at 1/5 and 8/15. The easiest way to make a common denominator is to multiply 1/5 by 15 on top and bottom. Also, we need to multiply 8/15 by 5 on top and bottom. HOwever, sometimes this gives us really big numbers...

So, the semi-easy way: What can I multiply 5 by (1/5th's denominator) to get 15 (8/15ths denominator)? That's right, 3.

Make sure to multiply top and bottom!

1/5 * 3/3 = 3/15 (multiply fractions straight across. top to top, bottom to bottom) Since 3/3 = 1, multiplying 1/5 * 3/3 doesn't change the value of it, just how we look at it.

So now it's easy to add! 5 and 3/15 (this was 1/5 from before) + 4 and 8/15

Add the whole numbers -> 5 + 4 = 9

then add the fractions -> 3/15 + 8/5 (add the tops, keep the bottom) -> 11/15

and we get 9 and 11/15ths