Class 11 • Maths • Chapter 14
PROBABILITY
True & False Quiz
Predict. Analyze. Quantify Uncertainty.
✓True
✗False
25
Questions
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Ch.14
Chapter
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XI
Class
Why True & False for PROBABILITY?
How this format sharpens your conceptual clarity
🔵 Probability is the mathematics of uncertainty — used in AI, finance, medicine, weather prediction, and decision-making systems.
✅ CBSE and JEE focus on classical probability, complements, and event logic — highly scoring with direct formulas.
🎯 Most errors happen in counting outcomes — especially in dice (36 outcomes), cards (52), and coin (2^n) problems.
📋
Read each statement carefully. Click True or False — instant feedback with explanation appears. Submit anytime; unattempted questions are marked Skipped.
Q 1
The probability of any event always lies between 0 and 1 (inclusive).
Q 2
The probability of a sure event is equal to 0.
Q 3
If an experiment has 10 equally likely outcomes, the probability of any one outcome is \(\frac{1}{10}\).
Q 4
If \(P(A)=0\), then \(A\) is an impossible event.
Q 5
If \(P(A)=1\), then \(A\) must occur.
Q 6
The probability of the sample space is always equal to 1.
Q 7
If two events are complementary, their probabilities add up to 2.
Q 8
If \(A\) and \(B\) are mutually exclusive, then \(P(A\cap B)=0\).
Q 9
For any event \(A\), \(P(A')=1-P(A)\).
Q 10
If outcomes are equally likely, classical probability can be applied.
Q 11
If \(P(A)=0.3\), then \(P(A')=0.7\).
Q 12
If two events are independent, then \(P(A\cap B)=P(A)+P(B)\).
Q 13
The probability of at least one event occurring is always greater than or equal to the probability of each event.
Q 14
If \(A\subset B\), then \(P(A)\le P(B)\).
Q 15
If \(P(A)=0.4\) and \(P(B)=0.5\), then \(P(A\cup B)=0.9\).
Q 16
If \(A\) and \(B\) are mutually exclusive, then they are also independent.
Q 17
If \(P(A|B)=P(A)\), then \(A\) and \(B\) are independent.
Q 18
For any two events, \(P(A\cup B)=P(A)+P(B)-P(A\cap B)\).
Q 19
If \(P(A)=0.6\), then \(P(A\cap A)=0.36\).
Q 20
If events are independent, occurrence of one affects the probability of the other.
Q 21
If three fair coins are tossed, the probability of exactly two heads is \(\frac{3}{8}\).
Q 22
If \(P(A)=0.5\), then \(P(A|A)=0.5\).
Q 23
If \(A\) and \(B\) are independent, then \(A'\) and \(B'\) are also independent.
Q 24
If \(P(A)=0.7\) and \(P(B|A)=0.2\), then \(P(A\cap B)=0.14\).
Q 25
If \(A\) and \(B\) are independent with \(P(A)=P(B)=0.5\), then \(P(A\cup B)=0.75\).
Key Takeaways — PROBABILITY
Core facts for CBSE Boards & JEE
1
P(E) = n(E)/n(S) —\text{ basic probability formula (equally likely outcomes).}
2
0 ≤ P(E) ≤ 1 —\text{ probability cannot be negative or greater than 1.}
3
P(E') = 1 - P(E) —\text{ use complement for “not” and “at least” questions.}
4
P(A ∪ B) = P(A) + P(B) - P(A ∩ B) —\text{ general addition rule.}
5
\text{Mutually exclusive }→ P(A ∪ B) = P(A) + P(B).
6
\text{Total outcomes: Coin} = 2^n, One die = 6, Two dice = 36, Cards = 52.