/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 44 The number of customers entering... [FREE SOLUTION] | 91Ó°ÊÓ

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The number of customers entering a store on a given day is Poisson distributed with mean \(\lambda=10 .\) The amount of money spent by a customer is uniformly distributed over \((0,100)\). Find the mean and variance of the amount of money that the store takes in on a given day.

Short Answer

Expert verified
The mean amount of money that the store takes in on a given day is \(500\), and the variance is \(83,333.3\).

Step by step solution

01

Find the expected value and variance of the amount of money spent by a single customer

Since the amount of money spent by a customer is uniformly distributed over \((0, 100)\), we can calculate the expected value (mean) and variance using the following formulas for a uniform distribution: Mean: \(E[X] = \frac{a + b}{2}\) Variance: \(Var(X) = \frac{(b - a)^2}{12}\) where \(X\) is the random variable representing the amount spent by a customer, and \(a\) and \(b\) are the lower and upper bounds of the distribution, respectively. In this case, \(a = 0\) and \(b = 100\). Mean: \(E[X] = \frac{0 + 100}{2} = 50\) Variance: \(Var(X) = \frac{(100 - 0)^2}{12} = \frac{10000}{12} = 833.33\)
02

Find the mean and variance of the amount of money that the store takes in on a given day

Given that the number of customers entering a store on a given day follows a Poisson distribution with mean \(\lambda = 10\), we can use the properties of the Poisson distribution and the expected value and variance calculated in Step 1 to find the mean and variance of the amount of money that the store takes in on a given day. Mean: \(E[Y] = \lambda E[X]\) Variance: \(Var(Y) = \lambda (Var(X) + E[X]^2) - \lambda^2 E[X]^2\) where \(Y\) is the random variable representing the amount of money that the store takes in on a given day. Mean: \(E[Y] = 10 \times 50 = 500\) Variance: \(Var(Y) = 10 (833.33 + 50^2) - 10^2 \times 50^2 = 10 (833.33 + 2500) - 10^2 \times 2500 = 10 \times 3333.33 - 250000 = 33333.3 - 250000 = 83,333.3\) Therefore, the mean amount of money that the store takes in on a given day is \(500, and the variance is \)83,333.3

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