Answer:
a) 
And replacing we got:

b)
And adding we got:
c) 
And replacing we got:

Step-by-step explanation:
Let X the random variable of interest "numebr of times that an alarm is triggered", on this case we now that:
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
Part a
We want to find this probability:

And replacing we got:

Part b

And adding we got:
Part c

And replacing we got:

Answer: (-3,1)
Step-by-step explanation:
The range is the set of possible output values, which are shown on the y-axis.
In my opinion, I like using improper fractions, but that's up to you:
7 1/5 = 36/5
6 2/5 = 32/5
36/5 - 32/5 = 4/5
Answer:
C 35:15
Step-by-step explanation:
because 35:15 =5:3 so it is not equal to a ratio of 5 is to 2