Mathematics for IGCSE & O level - Probability (Section 4 - No. 13)
If the probability of an event is 0.75, what is the probability that the event will *not* occur?
0.25
0.50
0.75
1.00
คำอธิบาย
The probability of not happening is 1 minus the probability of happening. 1-0.75=0.25