Answer:
a) E(X)=1
b) σ=1
c) P(X>1)=0.368
d) P(2<X<5)=0.128
Step-by-step explanation:
We have X: "the time between two successive arrivals at the drive-up window of a local bank", exponentially distributed with λ = 1.
a) We have to compute the expected time between two successive arrivals.
The expected value for X as it is exponentially distributed is:
b) We have to compute the standard deviation of X.
The standard deviation is calculated as:
c) The probability that X is larger than 1 (P(X>1))
We can express the probability as:
d) The probability that X is between 2 and 5 (P(2<X<5))
The answer is D: rectangle
Answer:
The answer is below
Step-by-step explanation:
a) Cost of hiring the bicycle for 14 days is:
Cost = 65 * 14 days + 44 = 954 riyals
b) The number of days the bicycle is hired is to be the same as the number of days the bicycle is to be hired. Let us assume that the bicycle and helmet is to be hired for x days, hence:
Cost of bicycle = 65 * x + 14 = 65x + 44
Cost of helmet = 12.5 * x = 12.5x
Total cost = 65x + 44 + 12.5x = 77.5x + 44
Since 750 riyals is available, hence:
750 = 77.5x + 44
77.5x = 706
x = 9.11
Therefore the maximum number of days is 11. The total cost for 11 days is:
Total cost = 77.5(9) + 44 = 741.5 riyals
Money not spent = 750 riyals - 741.5 riyals = 8.5 riyals
