1. ## Timezone math - which answer is right?

I was flying from London to Sydney with no stop-overs. I left London at 2:20 p.m. Tuesday (London time) and arrived in Sydney at 6:40 p.m. Wednesday (Syndey time). How long was the flight if Sydney is 11 hours ahead of London?

The answer i get is 17 hours, but the answer book says 17 hours 20 minutes.

If you get 17 hours 20 minutes please show the solution.

2. I'd be interested in seeing the work you did to get your answer, just look at the times, if one is 20 minutes after, the other is 40 minutes after, and the time zone shift is in even hour increments, how would it be possible to get 17 hours even? I think perhaps the way you're calculating the answer is actually 100% correct, but you're forgetting to carry that extra 20 minutes somewhere in your work.

3. Here's how I'd work this in my head:

2:20pm Tues to 2:20pm Wed = 24 hours
minus 11 hours (time zone change) = 13 hours
plus 4 hours 20 min (difference between 6:40pm and 2:20pm) = 17:20

4. Looks to me like the timezones are not really relevant to why Kick is getting that strange answer. I suspect he is adding the "20 minutes" and "40 minutes" rather than subtracting them.

5. If no time difference: 2:20pm (day1) to 6:40pm (day2) = 28 hours 20 minutes
Subtract time difference: 28h 20m - 11h 0m = 17h 20m