Question

Solved

Answer 1

What are the expected number of flights on time?

Answer 2

use proportions

Answer 3

Since 84% of the flights in the random sample are on time, we expect the same percentage to be on time in general. 84% means 84 out of 100.

Answer 4

Whoa..major lag

Answer 5

\(\dfrac{84}{100} = \dfrac{x}{203} \)

Answer 6

Your fav igreen! XD

Answer 7

I came up with .84 * 203 or 170.52

Answer 8

That sounds right

Answer 9

You can think of the proportion as follows:
84 flights out of 100 are on time just like x flights out of 203 are on time.

Answer 10

170.52

Answer 11

I was trying to say that before anyone else commented..for some reason I can only make one comment and it glitches and I have to reload..

Answer 12

Correct. I'd round it off to 171 because I don't know what 0.52 of a flight is.

Answer 13

Okay, now it asks:

"What is the standard deviation?"

Answer 14

Any idea on how to find that? @mathstudent55

Answer 15

What about you? @Astrophysics

Answer 16

Standard deviation is the average difference between any point of data and the mean, been a long time since I did statistics but I'm sure we can figure it out. \[\sigma = \sqrt{\frac{ 1 }{ N }\sum_{i=1}^{N}(x_i-\mu)^2}\]

Answer 17

But for this the easiest way I see is we can just use \[\sigma = \sqrt{npq}\] where \[\mu = \sqrt{np}\] that should be easy enough :P

Answer 18

Ahhh

Answer 19

I got 5.22

Answer 20

That sounds good!

Answer 21

\(\sf \sqrt{260 \times 0.84 \times 0.16}\)

Answer 22

Thanks!

Answer 23

Np