Tara baked 6 1/2 dozen cookies she sold 3 2/6 dozen of cookies she made how many dozens of cookies does tara have remaining

Convert the mixed numbers into improper fractions.
6 1/2= 13/2
3 2/6= 20/6
Now, find a common denominator. In this case, the common denominator is 6.
13/2*3/3=39/6
20/6 stays as 20/6
Subtract both fractions.
39/6-20/6=19/6
19/6 can be written as 3 1/6.
Tara has 3 1/6 dozen of cookies remaining.

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