Mathematics for IGCSE & O level - Probability (Section 6 - No. 37)
If the probability of an event happening is 0.2, what is the probability of that event *not* happening?
0.2
0.4
0.8
1.0
คำอธิบาย
The probability of an event not happening is 1 - probability of it happening. Therefore, 1 - 0.2 = 0.8.