Cards marked with numbers are placed in a box and mixed thoroughly. One card is drawn at random from the box. Find the probability that the number on the drawn card is a perfect square.
Answer
The correct answer is — Calculate the probability: .
Step-by-step solution
- Determine total outcomes: the numbers are from to inclusive, so .
- Identify the perfect squares between and : , , , and .
- Count the favorable outcomes: there are such numbers, so .
- Calculate the probability: .
Common mistake: Calculating for the total number of cards instead of adding to include both endpoints.
Concept tested: Probability with number cards
Published · How this solution was prepared and checked
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