Robert had 12 days of holiday. So, he had __________ minutes for his holidays.

The correct answer is: 17280

1 hr = 60 min, 24 hr = 24 × 60 = 1440 min (1 day)
Then 12 days = 12 × 1440 = 17280min

1 day= 24 x 60 minutes = 1440 minutes.
12 days = 12 x 1440 minutes= 17280 minutes.