Engineering Board Exam Reviewer · Basic Probability · medium
A number is chosen at random from the integers 1 to 100. What is the probability that it is divisible by 3 or by 5?
- 47/100
- 53/100
- 1/3
- 33/100
Answer
A. 47/100
Solution
Multiples of 3: 33. Multiples of 5: 20. Multiples of 15 (counted twice): 6. So 33+20-6=47 numbers, and P=47/100.
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