The task is to generate the correct answer for a given math problem.

[EX Q]: Problem: when positive integer n is divided by 5 , the remainder is 1 . when n is divided by 7 , the remainder is 3 . what is the smallest positive integer k such that k + n is a multiple of 40 .
[EX A]: 7

[EX Q]: Problem: a dishonest dealer professes to sell goods at the cost price but uses a weight of 800 grams per kg , what is his percent ?
[EX A]: 25 %

[EX Q]: Problem: the sum of first n consecutive odd integers is n ^ 2 . what is the sum of all odd integers between 15 and 41 inclusive .
[EX A]:
392