Preparing for the IIT JAM Statistics exam requires strong concepts and regular practice. One of the best ways to prepare for this exam is by solving IIT JAM Statistics previous year questions.

Previous year questions help students understand the exam pattern, difficulty level, and important topics. When you solve past questions, you become familiar with the type of problems that appear in the exam.

In this guide, we will discuss important IIT JAM Statistics previous year questions, their solutions, and tips to prepare effectively.

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Why Previous Year Questions Are Important

Many students focus only on theory books. However, solving past exam questions is equally important.

Benefits of solving previous year questions include:

• Understanding the exam pattern
• Learning important topics
• Improving problem-solving skills
• Increasing confidence for the exam

Students who practice past questions regularly often perform better in competitive exams.

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Question 1: Probability

Question

A bag contains 4 red balls and 6 blue balls. One ball is selected randomly. Find the probability that the ball is red.

Solution

Total balls = 4 + 6 = 10

Number of red balls = 4

Using probability formula:

P(A) = \frac{n(A)}{n(S)}$$P(\text{Red}) = \frac{4}{10}$$P(Red)=104​ $$P(\text{Red}) = 0.4$$P(Red)=0.4

Answer: Probability = 0.4

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Question 2: Mean

Question

Find the mean of the numbers:

8, 10, 12, 14, 16

Solution

Add the numbers:

8 + 10 + 12 + 14 + 16 = 60

Number of observations = 5

Mean formula:$$\bar{x} = \frac{\sum x}{n}$$xˉ=n∑x​ $$\bar{x} = \frac{60}{5}$$xˉ=560​ $$\bar{x} = 12$$xˉ=12

Answer: Mean = 12

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Question 3: Variance

Question

Find the variance of the data set:

2, 4, 6, 8

Step 1: Calculate mean.$$\bar{x} = \frac{2 + 4 + 6 + 8}{4}$$xˉ=42+4+6+8​ $$\bar{x} = 5$$xˉ=5

Step 2: Use variance formula.

\sigma^2 = \frac{1}{N}\sum_{i=1}^{N}(x_i – \mu)^2

x	x − μ	(x − μ)²
2	-3	9
4	-1	1
6	1	1
8	3	9

Sum = 20

Variance:$$\frac{20}{4} = 5$$420​=5

Answer: Variance = 5

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Question 4: Standard Deviation

Standard deviation is the square root of variance.$$\sigma = \sqrt{\sigma^2}$$σ=σ2​

Variance = 5$$\sigma = \sqrt{5}$$σ=5​

Answer: Standard deviation ≈ 2.24

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Question 5: Z-Score

Question

If mean = 70 and standard deviation = 10, find the Z-score of value 90.

$z = \frac{x – \mu}{\sigma}$z=σx−μ​

$x$x

$\mu$μ

$\sigma$σ

$z=\frac{x-\mu}{\sigma}\approx 0.333$z=σx−μ​≈0.333

$\Phi(z)\approx 63.1\%$Φ(z)≈63.1%

Where

• $x = 90$x=90
• $μ = 70$μ=70
• $σ = 10$σ=10

$$z = \frac{90 – 70}{10}$$z=1090−70​ $$z = 2$$z=2

Answer: Z-score = 2

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Question 6: Correlation

Question

If covariance between X and Y is 20, and standard deviations are 4 and 5, find the correlation coefficient.

Formula:$$r = \frac{Cov(X,Y)}{\sigma_x \sigma_y}$$r=σx​σy​Cov(X,Y)​

Substitute values:$$r = \frac{20}{4 \times 5}$$r=4×520​ $$r = 1$$r=1

Answer: Correlation coefficient = 1

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Question 7: Range

Question

Find the range of the dataset:

10, 15, 18, 22, 30

Range formula:

Maximum − Minimum

Maximum = 30
Minimum = 10$$Range = 30 – 10$$Range=30−10 $$Range = 20$$Range=20

Answer: Range = 20

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Important Topics in IIT JAM Statistics Previous Year Questions

Based on previous exams, some topics appear more frequently.

Important topics include:

• Probability
• Random variables
• Mean, median, mode
• Variance and standard deviation
• Correlation and regression
• Probability distributions

Students should focus more on these topics during preparation.

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Tips to Solve Previous Year Questions

Students should follow a clear strategy when solving past papers.

Understand the Question

Read the question carefully before solving.

Identify the Topic

Find the correct topic and formula required.

Solve Step by Step

Do not skip calculation steps.

Practice Regularly

Solve questions daily to improve speed.

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Best Strategy to Use Previous Year Questions

Students should use past papers in a smart way.

• Solve at least 10 years of previous papers
• Try solving questions without looking at solutions
• Analyze mistakes and learn from them
• Practice again after revision

This strategy helps students prepare effectively.

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Why Deep Institute Helps Students Prepare for IIT JAM

Preparing for IIT JAM can be challenging. Many students need guidance to understand statistics concepts.

Deep Institute provides:

• Structured IIT JAM Statistics study material
• Practice questions and solved papers
• Mock tests for exam preparation
• Expert faculty guidance
• Doubt solving sessions

These resources help students prepare confidently for the exam.

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Conclusion

Preparing for the IIT JAM Statistics exam requires strong concepts and regular practice. Solving IIT JAM Statistics previous year questions is one of the best ways to prepare for the exam.

Previous year papers help students understand the exam pattern and important topics. With regular practice and proper revision, students can improve their confidence and perform well in the IIT JAM Statistics exam.