If a whole number is divisible both by 6 and by 2 is it necessarily divisible by 12

The tuition costs, c, for a local community college are modeled by c(h) = 250 + 200h, where h represents the number of credit hours taken. the local state university has tuition costs, s, modeled by the function s(h) = 300 + 180h. how many credit hours will a student have to take for the two tuition costs to be equal? round the answer to the nearest tenth of an hour.

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If you have 12 feet of string and you cut it into equal length of 5 inches each how much string will be left