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The total value of daily sales made by salespeople at a large cell phone accessory shop can be described by a Normal distribution with mean = $333.73 and standard deviation = $63.84.

(a) What is the probability a randomly chosen salesperson will obtain a total value more than $378 in any given day? (4 decimals)
(b) As a reward for good performance, every day the salespeople with the highest 18% of total sales values get a free meal the following day. How much total sales value does a salesperson need in order to qualify for the free meal? (4 decimals)

User Dotnetstep
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Final answer:

To answer this question, we need to use the properties of the normal distribution. (a) The probability of a randomly chosen salesperson obtaining a total value more than $378 is approximately 0.2432. (b) A salesperson needs a total sales value of approximately $381.99 to qualify for the free meal.

Step-by-step explanation:

To answer this question, we need to use the properties of the normal distribution.

(a) To find the probability that a randomly chosen salesperson will obtain a total value more than $378, we need to find the area under the curve to the right of $378. We can use a standard normal distribution table or a calculator to find this probability. The z-score is calculated using the formula: z = (x - mean) / standard deviation. So, z = (378 - 333.73) / 63.84 = 0.6952. Looking up the z-score in the standard normal distribution table, we find that the probability is approximately 0.2432.

(b) To find the total sales value a salesperson needs to qualify for the free meal, we need to find the cutoff value that corresponds to the top 18% of the distribution. Again, we can use the standard normal distribution table or a calculator to find this cutoff value. The z-score corresponding to the top 18% is approximately 0.920 and can be found using the inverse normal function on a calculator. So, the salesperson would need a total sales value equal to: cutoff value * standard deviation + mean = 0.920 * 63.84 + 333.73 = $381.99 (approximately).

User Christina Foley
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