it is the last one im pretty sure
Answer: 0.3679
Step-by-step explanation:
The cumulative distribution function for exponential distribution is :-
, where
is the mean of the distribution.
Given : A mean length of waiting time equal
minutes
i.e. Mean number of calls answered in a minute 
Now, the proportion of callers is put on hold longer than 2.8 minutes is given by :_

Hence, the proportion of callers is put on hold longer than 2.8 minutes = 0.3679
(68 + 82 + 87 + 89 + x) / 5 > = 80
(326 + x) / 5 > = 80
326 + x > = 80 * 5
326 + x > = 400
x > = 400 - 326
x > = 74.......u would have to make at least a 74 to earn a B
Answer:
?=4
Step-by-step explanation:
?*(3+2)=12+8
?(5)=20
20/5=4
?=4
4*(5)=20
20=20
The answer to the missing value is X = 3