Answer:
36.58% probability that one of the devices fail
Step-by-step explanation:
For each device, there are only two possible outcomes. Either it fails, or it does not fail. The probability of a device failling is independent of other devices. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
A total of 15 devices will be used.
This means that 
Assume that each device has a probability of 0.05 of failure during the course of the monitoring period.
This means that 
What is the probability that one of the devices fail?
This is 


36.58% probability that one of the devices fail
Answer:
4
Step-by-step explanation:
1/3 of 30 students play sport
30×1/3
= 10
2/5 of this number plays soccer
10×2/5
= 20/5
= 4
Y=8/3x-10 is the answer in slope intercept form
We'll check if they're orthogonal:
u*v=0
(6,-2)*(8,24)=0
6*8+(-2)*24=0
48-48=0
0=0
they are orthogonal vectors