Solve the Problem. -Mark Can Remember Only the First 5 Digits of His

question 216

Multiple Choice

Solve the problem.
-Mark can remember only the first 5 digits of his friend's phone number. He also knows that the number has 7 digits and that the last digit is not a 0. If Mark were to dial all of the possible numbers
And if it takes him 25 seconds to try each one, how long would it take to try every possibility?

• A)37.5 minutes
• B)41.7 minutes
• C)4.2 minutes
• D)8.3 minutes

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Definitions:

Equal Chance

The principle or condition ensuring that all outcomes or members of a group have the same probability of occurrence or selection.

Central Limit Theorem

A statistical theory that states that, given a sufficiently large sample size, the distribution of the sample mean will be approximately normally distributed, regardless of the distribution of the parent population.

Sample Mean

The sample mean is the average value of a sample set, calculated by adding together all of the observations and dividing by the number of observations.

Skewed to the Right

Describes a distribution of data that has a tail extending to the right, indicating that the majority of data points are on the left.