Probability

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Practice Questions - Probability

 Q1) A coin is tossed 4 times, if tail occurs on first three tosses, find the probability of getting a head on the fourth toss. 1) 1/4 2) 1/16 3) 1/84) 1/2 Probability of getting a head on the fourth toss is 1/2. Hence, option 4. Q2) A dice is thrown three times, find the probability of getting a 3 on the third toss if it's given that 2 and 3 appear on first two tosses. 1) 1/22) 1/2163) 1/1084) 1/6 Probability of getting a 3 on the third toss is 1/6. Hence, option 4. Q3) A bag contains 4 blue, 4 yellow and 4 red balls. If three balls are drawn one by one without replacement, find the probability that none is blue. 1) 8/272) 14/553) 26/274) 1/3 Hence, option 2. Q4) If E and F are independent events such that P(E)=1/4 and P(F)=1/3 find P(not E and not F). 1) 1/22) 1/123) 7/124) 11/12 As E and F are independent events so P(not E and not F) = P(not E)P(not F) P(not E and not F) = (1 - 1/4)(1 - 1/3) = 1/2 Hence, option 1. Q5) Probability of A, B, C solving a problem is 2/5, 3/4 and 5/7 respectively. If a problem is given to all three then what is the probability that the problem is solved? 1) 67/702) 3/143) 11/144) 1 Hence, option 1.