Is 30 minutes a day enough?

Is working out 30 minutes a day for 5 days a week enough? I use the Nike Training Club app and i know this question probably depends on what type of exercises are done. Its a lot of cardio and lunges, squats, jogging etc. is 30 minutes a day for 5 days a week enough? thats 2 and a half hours a week. shuold i up it to three hours?