George weeded 2/5 of the garden and Tiffany weeded some, too when they were finished, 4/15 of the garden still needed to be weeded. What fraction of the garden did Tiffany weed?

1 Answer
Jan 13, 2017

Answer:

Tiffany weeded # 5/15 # of the garden.
#5/15# is equivalent to #1/3#.

Explanation:

George weeds #2/5# of the garden and #4/15# remains unweeded. It is difficult to compare fractions with different denominators. So it seems best to express #2/5# as an equivalent fraction like this: #2/5 = 2/5 . 3/3 = (2 . 3)/( 5. 3 )= 6/15#

We can now add the various bits:

Tiffany's bit + George's bit + unweeded bit #= # The whole garden .
Tiffany's bit#+ 6/15 + 4/15 = 15/15#

Tiffany's bit #+ 10/15 = 15/15#

So Tiffany's bit# = 5/15#
You can simplify this to # 1/3# by cancelling out the common factor 5.