Sidney flew in an airplane five times during her vacation.The flights averaged 2 hours 8 minutes long.The lengths of her first four flights were 2 hours 10 minutes,3 hours 20 mins,1 hours 15 minutesand 2hours 40 minutes.What was the length of her last flight

Answered this a couple of minutes ago below.

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To find the length of Sidney's last flight, we need to calculate the total time she spent on her first four flights and then subtract that from the total time spent on all five flights.

Let's add the lengths of her first four flights:
2 hours 10 minutes +
3 hours 20 minutes +
1 hour 15 minutes +
2 hours 40 minutes = 9 hours 25 minutes

Since this total includes the lengths of the first four flights, we can subtract it from the average length of all five flights to find the length of the last flight:
Average length of all five flights: 2 hours 8 minutes

Total time spent on all five flights: 5 flights * 2 hours 8 minutes per flight = 10 hours 40 minutes

Length of the last flight = Total time spent on all five flights - Total time spent on the first four flights
Length of the last flight = 10 hours 40 minutes - 9 hours 25 minutes = 1 hour 15 minutes

Therefore, the length of Sidney's last flight was 1 hour 15 minutes.