Which of the following cannot be a probability?
Show Hint
- \( \frac{2}{3} \)
- 15\%
- 0.7
- -1.5
The Correct Option is D
Solution and Explanation
Step 1: Understand the concept of probability
Probability is a measure of the likelihood of an event occurring. The probability of an event is always a number between 0 and 1, inclusive. That is: \[ 0 \leq P(\text{event}) \leq 1 \] A probability of 0 means the event cannot occur. A probability of 1 means the event will certainly occur.
Step 2: Analyze each option
Option (1): \( \frac{2}{3} \) is a valid probability, as it is a number between 0 and 1.
Option (2): 15% is equivalent to 0.15, which is a valid probability.
Option (3): 0.7 is a valid probability, as it is between 0 and 1.
Option (4): -1.5 is not a valid probability because probabilities cannot be negative.
Step 3: Conclusion
The only option that cannot be a probability is -1.5, as it falls outside the valid range for probabilities.
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