Is 10 minutes of exercise a day enough?

About 6/7 months a go I was exercising every day after 2 months i got very sick and stopped last 3 days I have started up exercising again, and have only been doing 10 minutes a day and in a week or so I plan on increasing it to 15 minutes, and going up each week by 5mins until I am at least doing 1 hour of exercise a day! I weigh 48kgs I'm 17 and I just want to have abs, nice butt, nice legs and arms (tonning) is 10 minutes a day enough or should I be pushing myself to do more, or just increase 5 minutes a week is what I am doing OK? And enough??