JEE Questions for Maths Probability Quiz 15

Two persons ‘A’ and ‘B’ have respectively n + 1 and n coin which they toss simultaneously. Then, the probability that A will have more heads than B is

0%
1/2
0%
>1/2
0%
<1/2
0%
None of these

Two dice are rolled one after the other. The probability that the number on the first is smaller than the number on the second is

0%
1/2
0%
7/18
0%
3/4
0%
5/12

A and B toss a fair coin each simultaneously 50 times. The probability that both of them will not get tail at the same toss is

0%
0%
2)
0%
0%

Three distinct numbers are selected from first 100 natural numbers. The probability that the three numbers are divisible by 2 and 3 is

0%
4/25
0%
4/35
0%
4/55
0%
4/1155

Three six faced fair dice are thrown together. The probability that the sum of the numbers appearing on the dice is k (3 ≤ k ≤ 8), is

0%
0%
2)
0%
0%
None of these

Out of 21 tickets marked with numbers from 1 to 21, three are drawn at random. The chance that the numbers on then are in AP is

0%
10/133
0%
9/133
0%
9/1330
0%
None of these

Three squares of a chess board the chosen at random, the probability that two are of one color and one of another is

0%
16/21
0%
8/21
0%
32/12
0%
None of these

A five digit number id formed by writing the digits 1, 2, 3, 4, 5 in a random order without repetitions. Then, the probability that the number is divisible by 4 is

0%
3/5
0%
18/5
0%
1/5
0%
6/5

If a party of n persons sit at a round table, then the odds against two specified individuals sitting next to each other are

0%
0%
2)
0%
0%

A complete cycle of a traffic light takes 60 seconds. During each cycle the light is green for 25 seconds, yellow for 5 seconds and red for 30 seconds. At a randomly chosen time, the probability that the light will not green is

0%
1/3
0%
1/4
0%
4/12
0%
7/12

A pair of fair dice is rolled together till a sum of either 5 or 7 is obtained. Then the probability that 5 comes before 7 is

0%
1/5
0%
2/5
0%
4/5
0%
None of these

Two dice are thrown simultaneously. The probability that sum is odd or less than 7 or both is

0%
2/3
0%
1/2
0%
3/4
0%
1/3

A student appears for test I, II and III. The student is successful is he passes either in test I and II or test I and III. The probabilities of the student passing in test I, II, III are p, q and 1/2 respectively. If the probability that the student is successful is 1/2, then

0%
0%
2)
0%
There are infinitely many values of p and q
0%
All of the above

For the three events A, B and C, P (exactly one of the events A or B occurs) = P(exactly one of the events B or C occurs) = P(exactly one of the events C or A occurs) = p and P (all the three events occur simultaneously) = p², where 0 < p < 1/2. Then the probability of at least one of the three events A, B and C occurring is

0%
0%
2)
0%
0%

0%
0%
2)
0%
0%

A box contains 100 tickets numbered 1, 2,…,100. Two tickets are chosen at random. It is given that the maximum number on the two chosen tickets is not more than 10. The minimum number on them is 5 with probability

0%
0%
2)
0%
0%
None of these

0%
0%
2)
0%
0%
None of these

A pack of playing cards was found to contain only 51 cards. If the first cards which are examined are all red, then the probability that the missing is black is

0%
0%
2)
0%
0%

If from each of the three boxes containing 3 white and 1 black, 2 white and 2 black, 1 white and 3 black balls, one ball is drawn at random, then the probability that 2 white and 1 black ball will be drawn is

0%
0%
2)
0%
0%

A fair coin is tossed n times. Let X be the number of times head is observed. If P(X = 4), P(X =and P(X =are in H.P., then n is equal to

0%
7
0%
10
0%
14
0%
None of these

0%
0%
2)
0%
0%
None of these

A man takes a step forward with probability 0.4 and backward with probability 0.6. The probability that at the end of eleven steps he is one step away from the starting point is