The task is to generate the correct answer for a given math problem.
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Question: Problem: a hiker walking at a constant rate of 4 kilometers per hour is passed by a cyclist travelling in the same direction along the same path at a constant rate of 24 kilometers per hour . the cyclist stops and waits for the hiker 5 minutes after passing her while the hiker continues to walk at her constant rate . how many minutes must the cyclist wait until the hiker catches up ?

Answer: 25


Question: Problem: mary can do a piece of work in 26 days . rosy is 30 % more efficient than mary . the number of days taken by rosy to do the same piece of work is ?

Answer: 20


Question: Problem: how many seven - digit numbers that do not contain the digits 2 or 9 are there ?

Answer:
183500