The answer is 8（x+1）。。。。。。
Answer:
Therefore, the probability that at least half of them need to wait more than 10 minutes is <em>0.0031</em>.
Step-by-step explanation:
The formula for the probability of an exponential distribution is:
P(x < b) = 1 - e^(b/3)
Using the complement rule, we can determine the probability of a customer having to wait more than 10 minutes, by:
p = P(x > 10)
= 1 - P(x < 10)
= 1 - (1 - e^(-10/10) )
= e⁻¹
= 0.3679
The z-score is the difference in sample size and the population mean, divided by the standard deviation:
z = (p' - p) / √[p(1 - p) / n]
= (0.5 - 0.3679) / √[0.3679(1 - 0.3679) / 100)]
= 2.7393
Therefore, using the probability table, you find that the corresponding probability is:
P(p' ≥ 0.5) = P(z > 2.7393)
<em>P(p' ≥ 0.5) = 0.0031</em>
<em></em>
Therefore, the probability that at least half of them need to wait more than 10 minutes is <em>0.0031</em>.
Answer:
42 mph
Step-by-step explanation:
From 2 p.m. to 6 p.m. 4 hours passed, so the truck and the motorcycle were on the road for 4 hours until they met.
Motorcycle in 4 hours at a constant speed of 45 mph travelled
The distance between the motorcycle and the truck is 348 miles, so the truck travelled
If x mph is truck's speed, then
Working for 2 hours pays $15.
Divide $15 by 2 to get $7.50 per hour.
Divide each amount of pay by its hours, and all are $7.50 per hour.
The equation is $7.50 multiplied by the number of hours, or
p = 7.50h
