math
posted by sam .
Ann bought 2/3 lb of carrots 3/4lb of celery and 7/8lb of onions. How many lbs of vegetables did she buy?

The question requires us to add three fractions, with different denominators.
The first step is to find a common denominator which is the LCM (least common multiple) among 3,4 and 8.
Since 4 divides 8, so 4 need not be accounted for. The LCM of 3 and 8 is just the product 24, since there are no common factors between 3 and 8.
Now convert all the fractions to the common denominator of 24, i.e.
2/3 = 16/24
3/4 = 18/24
7/8 = 21/24
Add the numerators and divide by the denominator to get
(16+18+21)/24=55/24= 2 11/24 lbs. 
thank you. Iget it know

You're welcome. :)
The method above is correct, but the final result should be 2 7/24 lbs, since 2*24=48, and 5548=7. Sorry for the oversight. 
Thanks