Learn

Saturday, 31 October

JEE Main 2022 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 27 July 2022, Shift 2, Maths Q17

Question 17 of 90 in this shift, Maths question 17 of 30, Section A.

A six faced die is biased such that 3×P(a prime number)=6×P(a composite number)=2×P(1)3 \times P(\text{a prime number}) = 6 \times P(\text{a composite number}) = 2 \times P(1). Let X be a random variable that counts the number of times one gets a perfect square on some throws of this die. If the die is thrown twice, then the mean of X is :
  1. (1)311\frac{3}{11}
  2. (2)511\frac{5}{11}
  3. (3)711\frac{7}{11}
  4. (4)811\frac{8}{11}Official answer

Official answer

Option 4

NTA final key.

Chapter
Probability
Topic
No close match in our taxonomy
Idea tested
No close match in our taxonomy

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.