MEDIUM
JEE Main
IMPORTANT
Earn 100

When a certain biased die is rolled, a particular face occurs with probability 16-x and its opposite face occurs with probability 16+x. All other faces occur with probability 16.

Note that opposite faces sum to 7 in any die. If 0<x<16, and the probability of obtaining total sum =7, when such a die is rolled twice, is 1396, then the value of x is

50% studentsanswered this correctly

Important Questions on Probability

MEDIUM
JEE Main
IMPORTANT
Each of the persons A and B independently tosses three fair coins. The probability that both of them get the same number of heads is:
EASY
JEE Main
IMPORTANT
An electric instrument consists of two units. Each unit must function independently for the instrument to operate. The probability that the first unit functions is 0.9 and that of the second unit is 0.8. The instrument is switched on and it fails to operate. If the probability that only the first unit failed and second unit is functioning is p, then 98p is equal to
MEDIUM
JEE Main
IMPORTANT
Let S={1, 2, 3, 4, 5, 6}. Then the probability that a randomly chosen onto function g from S to S satisfies g3=2 g1 is :
HARD
JEE Main
IMPORTANT

Two squares are chosen at random on a chessboard (see figure). The probability that they have a side in common is :

Question Image

MEDIUM
JEE Main
IMPORTANT

Let X be a random variable with distribution.

x -2 -1 3 4 6
P(X=x) 15 a 13 15 b

If the mean of X is 2.3 and variance of X is σ2, then 100σ2 is equal to :

HARD
JEE Main
IMPORTANT
Words with or without meaning are to be formed using all the letters of the word EXAMINATION. The probability that the letter M appears at the fourth position in any such word is:
HARD
JEE Main
IMPORTANT
The probability of selecting integers a-5,30 such that x2+2 a+4 x-5a+64>0, for all xR, is:
HARD
JEE Main
IMPORTANT
Let A, B and C be three events such that the probability that exactly one of A and B occurs is (1-k), the probability that exactly one of B and C occurs is (1-2k), the probability that exactly one of C and A occurs is (1-k) and the probability of all A, B and C occur simultaneously is k2, where 0<k<1. Then the probability that at least one of A, B and C occur is: