MCQ
The probability of guessing the correct answer to a certain question is $\frac{a}{b}$. If the probability of not guessing the correct answer to this question is 2/3, then
- Ab=4a
- ✓b=3a
- Cb=2a
- Db=a
✓
Answer
Correct option: B.
b=3a
(b) We have,
Probability of not guessing the correct answer to the question = $\frac{2}{3}$
∴Probability of guessing the correct answer to the question $=1-\frac{2}{3}=\frac{1}{3}$
$\Rightarrow \quad \frac{a}{b}=\frac{1}{3} \Rightarrow b=3 a$
Probability of not guessing the correct answer to the question = $\frac{2}{3}$
∴Probability of guessing the correct answer to the question $=1-\frac{2}{3}=\frac{1}{3}$
$\Rightarrow \quad \frac{a}{b}=\frac{1}{3} \Rightarrow b=3 a$
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