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.
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Question: Tim has 22 books. Mike has 20 books. How many books do they havetogether?

Answer: 42.0


Question: Oscar's bus ride to school is 0.75 mile and Charlie's bus ride is 0.25mile. How much longer is Oscar's bus ride than Charlie's?

Answer: 0.5


Question: Keith found 6 seashells, Jessica found 8 seashells, and Tim found 7seashells on the beach. When they cleaned them, they discoveredthat 3 were cracked. How many seashells did they find together?

Answer:
21.0