Exponential Distribution

Which of the following function represents a probability distribution function for an exponential distribution?

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The lifespan of a bulb is exponentially distributed with an average of 5 months.

If X represents the length of time of the lifespan of the bulb in months, what is the distribution of X?

The lifespan of a bulb is exponentially distributed with an average of 5 months.

If X represents the length of time of the lifespan of the bulb in months, what is the standard deviation of the distribution of X?

(Write the numeric answer only and leave out the units)

The lifespan of a bulb is exponentially distributed with an average of 5 months.

If X represents the length of time of the lifespan of the bulb in months, what is the decay parameter for the distribution of X?

The lifespan of a bulb is exponentially distributed with an average of 5 months.

If X represents the length of time of the lifespan of the bulb in months, what is the probability density function of the distribution of X?

The lifespan of a bulb is exponentially distributed with an average of 5 months.

If X represents the length of time of the lifespan of the bulb in months, what is the cumulative distribution function for X?

The lifespan of a bulb is exponentially distributed with an average of 5 months.

If X represents the length of time of the lifespan of the bulb in months, which graph shows the probability distribution function.

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On average, a certain computer part lasts ten years. The length of time the computer part lasts is exponentially distributed.

What is the probability that a computer part lasts more than 7 years?

(give your answer to 4 decimal places)

A customer service representative must spend different amounts of time with each customer to resolve various concerns. The amount of time spent with each customer can be modelled by the following distribution: X ~ Exp(0.125).

What is the mean of the mean?

A customer service representative must spend different amounts of time with each customer to resolve various concerns. The amount of time spent with each customer can be modelled by the following distribution: X ~ Exp(0.125).

What is the standard deviation?