You are provided with an arithmetic question. Your task is to compute the solution using the given arithmetic operations. The only arithmetic operators needed to answer the questions are'+'(addition) and'-'(subtraction). The answer should be correct to one decimal place.

[EX Q]: Dan has 64 violet marbles, he gave Mary 14 of the marbles. Howmany violet marbles does he now have?
[EX A]: 50.0

[EX Q]: Jason grew 37 watermelons and 30 pumpkins. Sandy grew 11watermelons. How many watermelons did they grow in total?
[EX A]: 48.0

[EX Q]: Sam found 18 seashells and Mary found 47 seashells on the beach.How many seashells did they find together?
[EX A]:
65.0