TASK DEFINITION: The task is to generate the correct answer for a given math problem.
PROBLEM: Problem: of the seven - digit positive integers that have no digits equal to zero , how many have two digits that are equal to each other and the remaining digit different from the other two ?

SOLUTION: 152409600

PROBLEM: Problem: a father said to his son , ' ' i was as old as you are at the present at the time of your birth ' ' . if the father ' s age is 52 years now , the son ' s age 5 years back was :

SOLUTION: d ) 21

PROBLEM: Problem: in the youth summer village there are 125 people , 50 of them are not working , 25 of them have families and 75 of them like to sing in the shower . what is the largest possible number of people in the village , which are working , that do n ' t have families and that are singing in the shower ?

SOLUTION:
75