Friday

August 28, 2015
Posted by **Kim** on Wednesday, May 1, 2013 at 3:33pm.

- 5th grade Math -
**Ms. Sue**, Wednesday, May 1, 2013 at 3:55pmYou must either

change the fractions to equivalent fractions with a common denominator

or

change the factions to equivalent decimals.

- 5th grade Math -
**Bosnian**, Wednesday, May 1, 2013 at 3:57pmIn google type :

add fractions with different denominators

You wil find many, many sites.

- 5th grade Math -
**Steve**, Wednesday, May 1, 2013 at 3:59pmcan't do it. Fractions with different denominators are different animals. Think of the denominator as a unit. A half is not the same as a third, just as apples are not oranges.

So, in order to add them, you need to convert them into the same units. To add 2/3 + 1/2, you have to make them somehow the same kind of thing.

If you cut a pie into 6 pieces, two of those pieces make 1/3, and 3 of them make 1/2. So, to do the addition, change things up so that

2/3 + 1/2

= 4/6 + 3/6

Now everything is the same kind of object: sixths

Now you can add them up

4/6+3/6 = 7/6 = 1 1/6

So, learn about something called the Lowest Common Denominator. To add fractions with different denominators, convert them so they are all multiples of the LCD. Then they can be added.

2/7 + 3/5 + 1/3

= 30/105 + 63/105 + 35/105

= 128/105