Statistics And Probability Question 170
Question: The probability of choosing at random a number that is divisible by 6 or 8 from among 1 to 90 is equal to:
Options:
A) $ \frac{1}{6} $
B) $ \frac{1}{30} $
C) $ \frac{11}{80} $
D) $ \frac{23}{90} $
Show Answer
Answer:
Correct Answer: D
Solution:
- [d] Nos. divisible by 6 are $ 6,12,18…90. $ Nos. divisible by 8 are $ 8,16,24…88. $ Now, total no. divisible by $ 6=15 $ And total no. divisible by $ 8=11 $ Now, the no. divisible by both 6 and 8 are 24, 48, 72. So, that no. divisibly by both 6 and $ 8=3 $
$ \therefore $ Probability (number divisible by 6 or 8) $ =\frac{15+11-3}{90}=\frac{23}{90} $