Class 12 Probability · Short Answer2 Marksfinite_sample_spaces
Class 12 Maths · Probability · Short Answer #40
Choose uniformly a card numbered 1 to 100. Find P(number divisible by 6 or 8, but not 24).
✅ Step-by-Step Solution
Final Answer: 1/5
- Let A,B be divisibility by 6,8. Counts are ⌊100/6⌋=16, ⌊100/8⌋=12; their intersection is divisibility by lcm(6,8)=24, count 4.
- The union has 16+12−4=24 elements. Removing the 4 multiples of 24 leaves 20.
- P=20/100=1/5.
📋 CBSE Stepwise Marking Scheme
- [0.5 marks] Let A,B be divisibility by 6,8. Counts are ⌊100/6⌋=16, ⌊100/8⌋=12; their intersection is divisibility by lcm(6,8)=24, count 4.
- [1 mark] The union has 16+12−4=24 elements. Removing the 4 multiples of 24 leaves 20.
- [0.5 marks] P=20/100=1/5.
Master Chapter 13: Probability
Practise interactive questions, flashcards, visual mind maps, and timed board tests for Probability.
← Previous Question
Prove that if E,F are independent, then E,F′ are independent.
Next Question →X has P(X=0)=k, P(X=1)=2k, P(X=2)=3k and zero elsewhere. Find k.
More Practice Questions in Probability
Related Questions in Probability
Class 12 Probability · Mcq Single Correct
Given P(A)=4/5 and P(A∩B)=7/10, find P(B|A).
Class 12 Probability · Mcq Single Correct
Five independent fair coins are tossed. Find the probability of at least one head.
Class 12 Probability · Mcq Single Correct
Given P(A|B)=0.3, P(A)=0.4, P(B)=0.8, find P(B|A).
Class 12 Probability · Mcq Single Correct
Two independent fair dice have sum 9. Find the conditional probability that at least one die…
Class 12 Probability · Mcq Single Correct
Choose an ordered pair (a,b) uniformly with distinct a,b from {1,2,3,4,5}. Find P(a/b is an…
Class 12 Probability · Mcq Single Correct
Given P(A)=0.4, P(B)=0.3 and P(A∪B)=0.5, find P(B′∩A).