Question 762057
Consider the following discrete probability distribution function for the variable X:
x
10
12
14
16
18
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f(x)
.02
.7
.05
.2
.03 
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P.s this is a table showing corresponding values of x and f(x) 
a) Is this a proper probability mass function? How do you know?
Each probability is between -1 and +1 
The sum of the probabilities = 1
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b) What is the probability that any draw from this distribution, say X, is less than 16 [i.e. find P(X<16)]?
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Ans: 0.02+0.70+0.05 = 0.75
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answers i arrived at but not sure about them yet; 
Yes this is a proper probability mas function because 0 < f(x) &#8804; 1 and the sum of all the f(x)values is 1 

The formula for probability is as follows;
P (E) = The Number Of Ways Event can occur/The total number Of Possible Outcomes 
The probability that P(X<16) =  0.02+0.70+0.05 = 0.75
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Cheers,
Stan H.
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