Definition: 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.
Input: Craig walked 0.2 mile from school to David's house and 0.7 mile fromDavid's house to his own house. How many miles did Craig walk in all?

0.9