Answer:
The probability that the time between the next two calls is between 3 minutes and 7 minutes is 0.2442.
Step-by-step explanation:
Let <em>X</em> = time between calls made to Amazon's customer service.
The average time between calls is, <em>β</em> = 10 minutes.
The random variable <em>X</em> follows an Exponential distribution with parameter 
The probability distribution function of <em>X</em> is:

Compute the probability that the time between the next two calls is between 3 minutes and 7 minutes as follows:

Thus, the probability that the time between the next two calls is between 3 minutes and 7 minutes is 0.2442.
Eric took 20 hours to do the job alone.
<u>Step-by-step explanation</u>:
<u>Given </u>:
- Total work = 75 packages
- Joe took 5 hours to complete the total work.
The amount of work Joe alone can do per hour = 75/5 = 15 packages.
The amount of work Joe and Eric together do per hour = 75/4 = 18.75
The amount of work Eric alone can do per hour = 18.75 - 15 = 3.75
The time Eric took to complete the entire work = 75 / 3.75 = 20 hours.
Answer:
d
Step-by-step explanation:
0.09/10=0.009
we check it: 0.009*10=0.09, so it's right
Answer:
22
Step-by-step explanation:
Mean basically just means average. To find the mean, add the numbers together and divide them by the number of numbers.
17 + 20 + 17 + 33 + 22 + 23 = 132
After that, divide by 6 since there are 6 numbers
132 ÷ 6 = 22
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Have a good day :)