The Probability That a Call Received by a Certain Switchboard

question 177

Multiple Choice

The probability that a call received by a certain switchboard will be a wrong number is 0.02.Use the Poisson approximation to the binomial distribution to find the probability that among 140 calls received by the switchboard,there are at least two wrong numbers.

• A)0.5305
• B)0.7616
• C)0.7689
• D)0.2384
• E)0.2311

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Definitions:

Standard Deviation

A measure of the dispersion or variability of a set of values, indicating how much they deviate from the mean.

Value

The worth, importance, or usefulness of something, often measured in terms of money, utility, or general significance.

Normal Random Variable

A variable following a normal distribution, characterized by a symmetric bell-shaped curve.

Variance

A measure of the dispersion or spread of a set of data points around their mean value, indicating the degree of variation from the average.