The task is to generate the correct answer for a given math problem.
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Question: Problem: there are 2 red chips and 3 blue ones . when arranged in a row , they form a certain color pattern , for example rbrrb . how many color patterns ?

Answer: e ) 10

Question: Problem: ( 935421 x 625 ) = ?

Answer: 584638125

Question: Problem: solve the equation 2 x = 2 b 2 ax , where a and b are real parameters . find for which values of a the equation has for solution a natural number , if b = 7

Answer:
1