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
sorry if I'm wrong. I got confused because you put 56+3 twice.×= 63
56+3=59=x-4 (this is with subtraction sign)
I didnt know if that a subtracting or negative so here both
56+3=x-4 (this is with the negative sign)
x= -14.75
I think the answer would be
X=1.5
Y= -10 or -12 or 12
Sorry I'm not sure
Answer: 16
Step-by-step explanation: