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Question 1:
Out of first 20 natural numbers, one number is selected at random. The probability that it is either an even number or a prime number is?
A. 1/2
B. 16/19
C. 4/5
D. 17/20
Feedback n(S) = 20
n(Even no) = 10 = n(E)
n(Prime no) = 8 = n(P)
P(EᴜP) = 10/20 + 8/20 - 1/20 = 17/20.

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