synthesisFR
School Spirit Skit 1
anyways so this question ruined my exam (0/4)
someone walk me through this pls
idk why i tried using sample proportion IDK WHATS GOING On
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- Thread starter synthesisFR
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anyways so this question ruined my exam (0/4)
someone walk me through this pls
idk why i tried using sample proportion IDK WHATS GOING On
raspberriesandpears
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- 2023
I'm not sure if I made illegal maths moves in the way I did it but I'll explain my thought process:
Obviously approximate via normal distribution, and place the mean as 17.5 (expected value of extra seats the airline can sell). The standard deviation was something like 4.08, and to ensure only 1% of flights can be over booked the z score was like 2.33 (for a 0.99 probability of success).
Just put those values into the z score formula then solve for x, which comes out to be 8; thus the airline can sell 358 seats.
It seemed a lot simpler than the answers hence my confusion but it seems okay to me? That's how I did it
Obviously approximate via normal distribution, and place the mean as 17.5 (expected value of extra seats the airline can sell). The standard deviation was something like 4.08, and to ensure only 1% of flights can be over booked the z score was like 2.33 (for a 0.99 probability of success).
Just put those values into the z score formula then solve for x, which comes out to be 8; thus the airline can sell 358 seats.
It seemed a lot simpler than the answers hence my confusion but it seems okay to me? That's how I did it
you’re just using the standard z score formula except unlike usually, you are trying to find the value for “n” (i.e. the number of tickets) based on other information. You can sub in 350 as the “x” because it’s what we’re trying to find the probability around, and then sub in the z score corresponding to the probability, the standard deviation as the root of npq and E(X)=0.95n (where n is our unknown pronumeral). From here you can either do quadratic formula like they did or inspection like I did, the rest is pretty trivial algebra.