Question

Robin randomly selects a number between 1 and 20. What is the probability that the number selected is the square of a natural number?

1/2
3/20
3/10
1/5
1/3

Answer 1

since there are only 1,4,9,16 that are squares, 4/20 = 1/5

Answer 2

Only 1,4,9,16
4/20 = 1/5

Answer 3

Betty picks 4 random marbles from a bowl containing 3 white, 4 yellow, and 5 blue marbles.
The probability that exactly 1 of the 4 marbles drawn is blue is . The probability that at least 1 of the 4 marbles drawn is white is .

Answer 4

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