Question

module 6: mastery
consumer mathematics - 81 / module 6 / lesson 99

1. jennifer is flying from montana to south carolina for vacation. her flight leaves at 6:30 a.m. mst. her flight is 3 hours. what time will she land in south carolina (est)?

○ 6:30 a.m. est
○ 8:30 a.m. est
○ 7:30 a.m. est
○ 11:30 a.m. est

Explanation:

Step1: Determine time zone difference

MST (Mountain Standard Time) is 2 hours behind EST (Eastern Standard Time). So when it's 6:30 a.m. MST, it's 8:30 a.m. EST (we add 2 hours for the time zone difference first).

Step2: Add flight duration

The flight is 3 hours long. Now, add 3 hours to 8:30 a.m. EST: 8:30 + 3 hours = 11:30 a.m. EST? Wait, no, wait. Wait, maybe I mixed up. Wait, no—wait, first, the flight departs at 6:30 a.m. MST, flight time is 3 hours, so arrival time in MST is 6:30 + 3 = 9:30 a.m. MST. Then convert MST to EST: MST is 2 hours behind EST, so EST is 2 hours ahead. So 9:30 a.m. MST + 2 hours = 11:30 a.m. EST? Wait, no, that's wrong. Wait, no—time zones: MST is UTC -7, EST is UTC -5. So EST is 2 hours ahead of MST. So when the flight leaves at 6:30 a.m. MST, the time in EST is 6:30 + 2 = 8:30 a.m. EST. Then the flight takes 3 hours, so arrival time in EST is 8:30 + 3 = 11:30 a.m. EST? Wait, but let's check the options. Wait, maybe I made a mistake. Wait, the options are 6:30, 8:30, 7:30, 11:30. Wait, maybe the time zone difference is 1 hour? No, MST is 2 hours behind EST (Mountain to Eastern: Eastern is ahead by 2 hours). Wait, let's re - calculate:

Departure time: 6:30 a.m. MST.

Flight duration: 3 hours. So arrival time in MST: 6:30 + 3 = 9:30 a.m. MST.

Now convert 9:30 a.m. MST to EST: since EST is 2 hours ahead of MST, add 2 hours: 9:30 + 2 = 11:30 a.m. EST. But wait, the options have 11:30 a.m. EST as an option. Wait, but maybe I messed up the time zone direction. Wait, no—if you are going from MST to EST (eastward), you gain time. So when it's 6:30 a.m. MST, EST is 8:30 a.m. (6:30 + 2). Then the flight takes 3 hours, so 8:30 + 3 = 11:30 a.m. EST. So the answer should be 11:30 a.m. EST.

Wait, but let's check again. Alternatively, maybe the problem considers that when you fly from MST to EST, the time zone change is accounted for in the flight. Wait, no—flight time is the duration in the air, and then we have to convert the arrival time in the destination's time zone. So departure: 6:30 a.m. MST, flight 3 hours, so arrival in MST is 9:30 a.m. MST. Then EST is 2 hours ahead, so 9:30 + 2 = 11:30 a.m. EST. So the correct option is 11:30 a.m. EST.

Answer:

11:30 a.m. EST (the option with "11:30 a.m. EST")