Answer:
3.3333 hours
Explanation:
From the attached table :
Downhill skiing for 1/6 hours ; results in 100 calories burn
To burn 1000 calories :
Skiing hours required :
(1000 / 100) * (1/6)
10 * 1/6 = 10 /6 hours
Planned skiing hours = 5
Number of skiing hours after lunch will be :
5 hours - 10/6 hours
5 hours - 1.6666 hours
= 3.3333 hours