The time between calls made to Amazon's customer service is exponentially distributed with a mean of 10 minutes (taken between each two successive calls). The probability that the time between the next two calls is between 3 minutes and 7 minutes is:

A. 0.7558
B. 0.5034
C. 0.2442
D. 0.2592

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 X = time between calls made to Amazon's customer service.

The average time between calls is, β = 10 minutes.

The random variable X follows an Exponential distribution with parameter

The probability distribution function of X 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.

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!

7.3

step-by-step explanation: