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.

A spaceship traveled 0.5 light-year from Earth to Planet X and 0.1light-year from Planet X to Planet Y. Then it traveled 0.1 light-yearfrom Planet Y back to Earth. How many light-years did the spaceshiptravel in all?
0.7