Probability Questions With Answers

A coin is thrown 3 times .what is the probability that atleast one head is obtained?

Sample space = [HHH, HHT, HTH, THH, TTH, THT, HTT, TTT] Total number of ways = 2 × 2 × 2 = 8.  Fav. Cases = 7 P (A) = 7/8

Find the probability of getting a numbered card when a card is drawn from the pack of 52 cards.

Total Cards = 52. Numbered Cards = (2, 3, 4, 5, 6, 7, 8, 9, 10) 9 from each suit 4 × 9 = 36 P (E) = 36/52 = 9/13

There are 5 green 7 red balls. Two balls are selected one by one without replacement. Find the probability that first is green and second is red.

P (G) × P (R) = (5/12) x (7/11) = 35/132

What is the probability of getting a sum of 7 when two dice are thrown?

Probability math - Total number of ways = 6 × 6 = 36 ways. Favorable cases = (1, 6) (6, 1) (2, 5) (5, 2) (3, 4) (4, 3) --- 6 ways. P (A) = 6/36 = 1/6

hree dice are rolled together. What is the probability as getting at least one '4'?

Total number of ways = 6 × 6 × 6 = 216. Probability of getting number ‘4’ at least one time = 1 – (Probability of getting no number 4) = 1 – (5/6) x (5/6) x (5/6) = 91/216

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