Jack hit a combined 18 doubles and triples last baseball season. A double is two bases and a triple is three bases. If he had 42 total bases in these 18 hits, how many of these hits were triples?

The length of a rectangular board is 3 feet less than twice its width. a second rectangular board is such that each of its dimensions is the reciprocal of the corresponding dimensions of the first rectangular board. if the perimeter of the second board is one-fifth the perimeter of the first, what is the perimeter of the first rectangular board?