The task is to generate the correct answer for a given math problem.
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Question: Problem: a is twice as good a workman as b and they took 6 days together to do the work b alone can do it in .

Answer: 18 days


Question: Problem: set s contains exactly 10 numbers and has an average ( arithmetic mean ) of 6.2 . if one of the numbers in set s is increased by 7 , while all other numbers remain the same , what is the new average of set s ?

Answer: 6.


Question: Problem: how many 3 digit numbers n are divisible by 78 or 91 ?

Answer:
19