Q 1. (a) Cars on a toll road arrive at the payment booth at an average rate of 80 per) hour. What is the probability of no cars arriving in an interval of 2.5 minutes?
(b) At the same toll booth what is the probability that the time to the next car arriving will be between one and two minutes?
Q 2.
|
Rate (N)
|
Frequency
|
|
32.5
|
3 |
|
33.0
|
7 |
|
33.5
|
15 |
|
34.0
|
13 |
|
34.5
|
20 |
|
35.0
|
18 |
|
35.5
|
17 |
|
36.0
|
3 |
|
36.5
|
3 |
|
37.0
|
1 |
(a) Does it seem that the "rates" are Normally distributed? (Provide clear evidence for your conclusion).
(b) If the distribution were Normal. what proportion of all springs would be expected to lie outside the specification?
(c) From the sample, does it seem that the population mean is on target?