Some please help me help my son -> I need to add fractions and I've been out of school for a long time...

Question

Could you please explain how you come to an answer with the following problem:

(A) 2/3 + 5/6 + 11/12 and

(B) 2 3/4 + 1 1/5

Thank you so much for your help! I'm stuck and my son and I are going nuts trying to figure this out.

Answer 1

A) 2/3 + 5/6 + 11/12

Firts we reduce to common denominator:
LCM ( 3, 6, 12) = 12

Now divide 12 per the denominator of each fraction and multiply the result by the numerator of each one:
2*4/12 + 5*2/12 + 11/12 =
8/12 + 10/10 + 11/12 =

Now sum the numerators:
(8 + 10 + 11) / 12 =
= 29/12
= (24 + 5) / 12
= 24/12 + 5/12
= 2 5/12

B) 2 3/4 + 1 1/5
(2*4 + 3)/4 + (1*5 + 1)/5
= 11/4 + 6/5
We reduce to common denominator:
LCM ( 4, 5) = 20

Now divide 20 per the denominator of each fraction and multiply the result by the numerator of each one:
= 11*^5/20 + 6*4/20
= 55/20 + 24/20
= (55+24)/20
= 79 / 20
= (60 + 19)/20
= 60/20 + 19/20
= 3 19/20

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Solutions:
A) 29/12 = 2 5/12
B) 79/29 = 3 19/20
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Bye and Good Luck !!
>(^_^)<

Answer 2

First you have to find the lowest common denominator.

A)2/3 + 5/6 + 11/12

The lowest common denominator that all could go into evenly is 12

2/3 = 8/12 because 3 goes into 12, 4 times, then you multiply the numerator by 4 2x4 =8

5/6 = 10/12 because 6 goes into 12 2 times, then you multiply the numerator by 5 2x5= 10

11/12 stays as is because it already has the lowest common denominator.

now you add 8/12 + 10/12 + 11/12 = 29/12... if you need to round it off it will be 2 5/12

B)2 3/4 + 1 1/5

you need to find the lowest common denominator which is 20

2 3/4 becomes 2 15/20 because you leave the whole number alone, and since 4 goes into 20 5 times, you multiply the numerator 3 by 5 = 15

1 1/5 becomes 1 4/20 because you leave the whole number alone, and since 5 goes into 20 4 times, you multiply the numerator 1 by 4 = 4

now you add 2 15/20 + 1 4/20 = 3 19/20



I hope i did not confuse you more.

here is a great webpage that can help you:

http://www.themathpage.com/ARITH/add-fractions-subtract-fractions-1.htm

Answer 3

You already have a few good answers but I thought more info might help....

So to add any nuber of fractions together they have to have the same number on the bottom of the fraction. So with the 2/3, 5/6 and 11/12 the easyist number to have on the bottom of all of them would be 12.... In order to do this you would multiply both the top and the bottom of each fraction that is not already set over 12 by what ever number is needed to make that bottom part 12. (this is ok to do because any number over itseld is equal to 1 and any number times 1 is that number)

So you would take 2/3 and multilply by 4/4 and get 8/12
then take 5/6 and muliply by 2/2 and get 10/12

then just add 8/12 + 10/12 + 11/12 = 8+10+11/12 = 29/12 or 2 5/12

Answer 4

You need to find a common denominator.
A. 2/3 + 5/6 + 11/12
8/12+10/12+11/12
Now just add the numerators and leave the denominator the same.
8+10+11=29 = 29/12= 2 5/12

b.Change mixed number into fraction
2 3/4+ 1 1/5=
11/4+6/1=
11/4+24/4=35/4= 8 3/4...

I THINK LOL

Answer 5

you make them have comon denomenators(the bottom #)then add
A)8/12+ 10/12 + 11/12= 29/12 = 2 5/12
thats the first 1 mabey you can figure out the second by your self and if not email me

Answer 6

The system is to be approached by findng the LOWEST COMMON DENOMENATOR. And then WE add the numerators above that denomenator.


But what exactly is the "system"? We are adding the divided parts of ONE whole; in the first case twelfths and in the second, twentieths.



Kristoff

Answer 7

Here, check the part on "adding fractions:"

http://en.wikipedia.org/wiki/Fraction_%28mathematics%29

Answer 8

it's hard to explain into words, if u'd like, i can handwrite and scan/email the process...email me if ur interested