Introduction to Statistical Methods for the Life and Health Sciences
x | P(X≤x) | x | P(X ≤ x) | x | P(X ≤ x) |
15 | 0.0000 | 20 | 0.0668 | 25 | 0.8413 |
16 | 0.0002 | 21 | 0.1587 | 26 | 0.9332 |
17 | 0.0013 | 22 | 0.3085 | 27 | 0.9772 |
18 | 0.0062 | 23 | 0.5000 | 28 | 0.9938 |
19 | 0.0228 | 24 | 0.6915 | 29 | 0.9987 |
P(X ≤ x) | x |
0.1000 | 6.9596 |
0.2500 | 7.7367 |
0.7500 | 9.4633 |
0.9000 | 10.2404 |
(i) What is the least amount of soft serve ice cream that is needed so that the driver can satisfy demand on 90% of afternoons? Z=(X-8.6)/1.28, Z (90%) = 1.28. Solve for X!
SD(Y) = Sqrt( 225 + 81) = 17.5
(ii) What can we say about the shape of the distribution of Y? If X and W are normally distributed, then so is Y!