GATE · Engineering Mathematics

Probability

15 practice questions, each with the answer and an explanation.

Practise Probability now

Random questions from this topic, one at a time. You see the answer and the explanation straight after each one.

All 15 questions

  1. A continuous random variable has the probability density function for , and elsewhere. What is the conditional probability ?
  2. Two fair dice are thrown. What is the probability that the sum of the numbers is ?
  3. Two fair dice are thrown. What is the probability that the sum of the numbers is ?
  4. Two fair dice are thrown. What is the probability that the sum of the numbers is ?
  5. Two fair dice are thrown. What is the probability that the sum of the numbers is ?
  6. Two fair dice are thrown. What is the probability that the sum of the numbers is ?
  7. Two fair dice are thrown. What is the probability that the sum of the numbers is ?
  8. If and are independent events with and , find .
  9. If and are independent events with and , find .
  10. A machine produces bolts with a 2% defect rate. In a random sample of 100 bolts, what is the probability of finding exactly 2 defective bolts using the Poisson approximation?
  11. Two fair six-sided dice are rolled simultaneously. Given that the sum of the numbers is greater than 8, what is the conditional probability that the numbers are equal?
  12. A continuous random variable X has probability density function f(x) = k * x^2 for 0 ≤ x ≤ 2, and 0 elsewhere. What is the expected value E[X]?
  13. In a communication system, bit 0 is transmitted with probability 0.6 and bit 1 with 0.4. Due to channel noise, a transmitted 0 is received as 1 with probability 0.1, and a transmitted 1 is received as…
  14. If X and Y are independent random variables each uniformly distributed on [0, 1], what is the probability P(X + Y ≤ 1)?
  15. The variance of a binomial random variable with parameters n = 100 and p = 0.2 is:

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