Answer:
P(Not a 3)=0.85. This is option C.
Explanation:
P(Not a 3) would include values 1,2 and 4.
Therefore, P(Not a 3) would be the combined totals of the probabilities of P(1), P(2) and P(4).
P(Not a 3)= P(1)+P(2)+P(4)
P(Not a 3)= 0.30+0.40+0.15
P(Not a 3)=0.85
Alternate method
P(Not a 3) is the same as 1-P(3)
P(Not a 3)=1-P(3)
P(Not a 3)= 1-0.15
P(Not a 3)=0.85