How long would it take to lose 40lbs if you burn over 600 calories a day and are eating right?

233 days assuming you burn 600 calories per day:*

1 lb = 3,500 calories

40 x 3,500 = 140,000 calories

140,000 / 600 = 233 days

*The actual number may be less if you are working out because muscle continues to burn calories after workouts.