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

Problem: each digit 1 through 5 is used exactly once to create a 5 - digit integer . if the 3 and the 4 can not be adjacent digits in the integer , how many 5 - digit integers are possible ?
72

Problem: of 30 applicants for a job , 9 had at least 4 years ' experience , 18 had degrees , and 3 had less than 4 years ' experience and did not have a degree . how many of the applicants had at least 4 years ' experience and a degree ?
10

Problem: a man can swim in still water at 3 km / h , but takes twice as long to swim upstream than downstream . the speed of the stream is ?