Answer:
a) 50.34% probability that the arrival time between customers will be 7 minutes or less.
b) 24.42% probability that the arrival time between customers will be between 3 and 7 minutes
Step-by-step explanation:
Exponential distribution:
The exponential probability distribution, with mean m, is described by the following equation:

In which
is the decay parameter.
The probability that x is lower or equal to a is given by:

Which has the following solution:

The probability of finding a value higher than x is:

Mean of 10 minutes:
This means that 
A. What is the probability that the arrival time between customers will be 7 minutes or less?


50.34% probability that the arrival time between customers will be 7 minutes or less.
B. What is the probability that the arrival time between customers will be between 3 and 7 minutes?





24.42% probability that the arrival time between customers will be between 3 and 7 minutes
She would have to work 11 hours to get enough money to buy the sneakers
But if you want the hours included for the time she needs to work to pay off the loan she would have to work 8 hours, so all together 19 hours.
Hope this helps!!
The range of the equation is 
Explanation:
The given equation is 
We need to determine the range of the equation.
<u>Range:</u>
The range of the function is the set of all dependent y - values for which the function is well defined.
Let us simplify the equation.
Thus, we have;

This can be written as 
Now, we shall determine the range.
Let us interchange the variables x and y.
Thus, we have;

Solving for y, we get;

Applying the log rule, if f(x) = g(x) then
, then, we get;

Simplifying, we get;

Dividing both sides by
, we have;

Subtracting 7 from both sides of the equation, we have;

Dividing both sides by 2, we get;

Let us find the positive values for logs.
Thus, we have,;


The function domain is 
By combining the intervals, the range becomes 
Hence, the range of the equation is 
I think its 92 but im not entirely sure. hope it helps though