Mr. John jogs for 1 hour 30 minutes in the morning every day. How much time (in hours) will he have spent jogging after two weeks? Let's think first. Chain of thought:
There are 60 minutes in an hour so 1 hour 30 minutes is equivalent to [1 + (30 / 60)] hours = 1.5 hours. There are 7 days in a week so he spends 1.5 * 7 = 10.5 hours jogging every week. After 2 weeks he will have spent 2 * 10.5 = 21 hours jogging.
Therefore, the answer is 21.