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

Answer: 152409600


Question: Problem: a cistern 12 m long and 14 m wide contains water up to a depth of 1 m 25 cm . the total area of the wet surface is :

Answer: 233 m 


Question: Problem: two brother x and y appeared for an exam . the probability of selection of x is 1 / 3 and that of b is 2 / 7 . find the probability that both of them are selected .

Answer:
2 / 21