If the time of a place is 10 a.m., what will be the local time of a place 2° to its west?

Correct answer: c 9:52

2 × 4 = 8 minutes; subtracting for the west, 10:00 − 8 minutes = 9:52.

Why the other options are wrong

• a 10:04: This goes east and takes 2 minutes per degree; in the west time is less, and 1° = 4 minutes.
• b 10:08: 10:08 would be 2° to the east; in the west 8 minutes are subtracted.
• d 9:58: This takes 1 minute per degree; the book says 4 minutes per degree.