Mathematics · 2020
JEE Main · 9 January 2020, Shift 1 · Q67
In a box, there are 20 cards, out of which 10 are labelled as A and the remaining 10 are labelled as B. Cards are drawn at random, one after the…
In a box, there are $\displaystyle 20$ cards, out of which $\displaystyle 10$ are labelled as A and the remaining $\displaystyle 10$ are labelled as B. Cards are drawn at random, one after the other and with replacement, till a second A-card is obtained. The probability that the second A-card appears before the third B-card is :
Official answer
(3)
$\displaystyle \frac{11}{16}$
More from Probability
- Let A and B be two independent events such that P(A)=1/3 and P(B)=1/6. Then, which of the following is TRUE?2020
- Bag B_1 contains 6 white and 4 blue balls, Bag B_2 contains 4 white and 6 blue balls, and Bag B_3 contains 5 white and 5 blue balls. One of the bags…2025
- Let S={M=[a_i j], a_i j ∈{0,1,2}, 1 ≤ i, j ≤ 2} be a sample space and A={M ∈ S: M is invertible } be an event. Then P(A) is equal to2023
- In a bombing attack, there is 50\% chance that a bomb will hit the target. At least two independent hits are required to destroy the target…2020
- Bag A contains 9 white and 8 black balls, while bag B contains 6 white and 4 black balls. One ball is randomly picked up from the bag B and mixed up…2026
- Three urns A, B and C contain 4 red, 6 black; 5 red, 5 black; and λ red, 4 black balls respectively. One of the urns is selected at random and a ball…2023
- A candidate has to go to the examination centre to appear in an examination. The candidate uses only one means of transportation for the entire…2026
- The coefficients a, b and c of the quadratic equation, a x^2+b x+c=0 are obtained by throwing a dice three times. The probability that this equation…2021
JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.