



 
Hi Clara. If you factor k/240, you can get this: k/240 = k x (1/5 x 1/2 x 1/2 x 1/2 x 1/2 x 1/3) A terminating decimal times any other terminating decimal always equals a terminating decimal. Since 1/5 and 1/2 are terminating decimals, I know that (1/5 x 1/2 x 1/2 x 1/2 x 1/2 x 1/3) = 1/80 is a terminating decimal. Clearly, k is an integer, so that terminates. Thus k/80 must be a terminating decimal. This leaves just the question then of when k/80 x 1/3 is a terminating decimal. Can you finish the problem now? Cheers,  


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