PLEASE HELP! Its pretty simple. Mr. Simon baked a pie for his two daughter. He and his wife each ate 1/10 (0.1), and his daughters had 2/5 (0.4) of the pie (combined). How much of the pie remains?

Aresearcher believes increased perceived control influence the well-being of residents at a nursing home. to test this , she allowed one group of residents to have control over their daily lies, (where to eat etc) . the other group of 5 residents had these deceisions made by staff. the resident's feelings of well-being were measured on a 10 point scale at the end of a one month trial period. is there a difference on well-being?