A basket contains 15 white balls, 25 red balls and 10 blue balls. If a ball is selected at random, the probability of selecting not a white ball.

Option d: 0.70. Solution: Probability of Not Selecting a White Ball Given: - White balls = 15 - Red balls = 25 - Blue balls = 10 - Total balls = 15 + 25 + 10 = 50 Favorable outcomes (not white) = 25 + 10 = 35 P(not white) = 35/50 = 0.70 Alternatively: P(white) = 15/50 = 0.30 P(not white) = 1 - 0.30 = 0.70 Hence, Option D is the correct answer.

A basket contains $15$ white balls, $25$ red balls and $10$ blue balls. If a ball is selected at random, the probability of selecting not a white ball.

The correct answer is Option d: 0.70. **Probability of Not Selecting a White Ball** Given: - White balls = 15 - Red balls = 25 - Blue balls = 10 - Total balls = $15 + 25 + 10 = 50$ Favorable outcomes (not white) = $25 + 10 = 35$ $$P(\text{not white}) = \frac{35}{50} = 0.70$$ Alternatively: $$P(\text{white}) = \frac{15}{50} = 0.30$$ $$P(\text{not white}) = 1 - 0.30 = 0.70$$ Hence, **Option D** is the correct answer.

ProbabilityMCQPYQ Jan. 21Question 3278 of 187

All Questions

A basket contains $\displaystyle 15$ white balls, $\displaystyle 25$ red balls and $\displaystyle 10$ blue balls. If a ball is selected at random, the probability of selecting not a white ball.

Options

A0.20

B0.25

C0.60

D0.70

For any discrepancies in this question, email contact@cadada.in

Correct Answer

✅ Option d — 0.70

All Options:

A0.20
B0.25
C0.60
D0.70

Detailed Solution & Explanation

**Probability of Not Selecting a White Ball** Given: - White balls = 15 - Red balls = 25 - Blue balls = 10 - Total balls =

\displaystyle 15 + 25 + 10 = 50

Favorable outcomes (not white) =

\displaystyle 25 + 10 = 35

P(\text{not white}) = \frac{35}{50} = 0.70

Alternatively:

P(\text{white}) = \frac{15}{50} = 0.30

P(\text{not white}) = 1 - 0.30 = 0.70

Hence, **Option D** is the correct answer.

About This Chapter: Probability

Paper

Paper 3: Quantitative Aptitude

Weightage

5-7 Marks

Key Topics

Probability Operations, Expected Value

A logic-heavy chapter dealing with random experiments, events (mutually exclusive, exhaustive), set theory probability, conditional probability, and Bayes' Theorem. It forms the basis for Theoretical Distributions.

View Official ICAI Syllabus

Exam Strategy Tip

Always draw a quick Venn Diagram or tree when faced with 'At least one' or 'Only A but not B' wording. It saves you from double-counting.

Key Concepts to Understand

Probability

A numerical measure of the likelihood of an event occurring, expressed as a number between 0 (impossible) and 1 (certain). Formula: P(A) = Number of favorable outcomes / Total number of equally likely outcomes.

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A basket contains 15\displaystyle 1515 white balls, 25\displaystyle 2525 red balls and 10\displaystyle 1010 blue balls. If a ball is selected at random, the probability of selecting not a white ball.