Statistics Questions with Solutions
Statistics deals with collecting, summarising and interpreting data. This topic covers measures of central tendency (mean, median and mode) for ungrouped and grouped data, and measures of dispersion such as range, mean deviation, variance, standard deviation and the coefficient of variation. Exam questions test calculating these measures, the effect of adding or multiplying every observation by a constant, combined mean and variance of two groups, and comparing the consistency of two data sets. Remember that adding a constant to every value changes the mean but not the variance or standard deviation, while multiplying by k multiplies the standard deviation by |k|. Facts like these solve many questions without any calculation. Practise the statistics questions below, each with a step-by-step solution.
- Q1.
The distances in metres for seven throws of a shot-putter are: 14.5, 15.2, 16.8, 17.1, 15.9, 16.3, 14.7. Calculate the sample mean and sample standard deviation. Round to two decimals.
A. 15.79, 1.02B. 15.79, 0.96C. 14.79, 1.15D. 14.79, 0.88mediumAsked in NIMCET 2026View solution āŗ - Q2.
Consider the following grouped data. Find the mode. Class interval: 20ā25, 25ā30, 30ā35, 35ā40, 40ā45, 45ā50 Number of students: 8, 14, 20, 18, 10, 6
A. 32.14B. 31.67C. 33.75D. 34.12easyAsked in NIMCET 2026View solution āŗ - Q3.
An investigator has missed a value while collecting data in an experiment. Denoting the missing value by , the observations are: 10, 4, 11, 6, 17, 15, 9, 8, . What should be the value of , if he wants mean = median = mode for this data set?
A. 9B. 10C. 11D. 12mediumAsked in NIMCET 2026View solution āŗ - Q4.
For a given sample, the computed values of the variance and fourth central moment are 3 and 63 respectively. Then the underlying frequency distribution is classified as:
A. NormalB. MesokurticC. PlatykurticD. LeptokurticeasyAsked in NIMCET 2026View solution āŗ - Q5.
The mean of 5 observations is 5 and their variance is 12.4. If three of the observations are 1, 2 and 6, then the mean deviation from the mean of the data is:
A. 2.5B. 2.6C. 2.8D. 2.4mediumAsked in NIMCET 2023 +1View solution āŗ - Q6.
For a group of 100 candidates, the mean and standard deviation of scores were found to be 40 and 15 respectively. Later on, it was found that the scores 25 and 35 were misread as 52 and 53 respectively. Then the corrected mean and standard deviation are
A. 39.9, 14.97B. 39.5, 14C. 39.55, 14.97D. 40.19, 15.1mediumAsked in NIMCET 2023View solution āŗ - Q7.
Consider the following frequency distribution table. Class interval 10-20 20-30 30-40 40-50 50-60 60-70 70-80 Frequency 180 34 180 136 50 If the total frequency is 685 and the median is 42.6, then the values of and are
A. 80, 25B. 83, 22C. 79, 26D. 82, 23hardAsked in NIMCET 2023View solution āŗ - Q8.
If and are the means of two distributions such that and is the mean of the combined distribution, then
A. B. C. D.easyAsked in NIMCET 2013View solution āŗ - Q9.
If the mean of the squares of the first natural numbers is , then is equal to
A. B. C. D.easyAsked in NIMCET 2011 +1View solution āŗ - Q10.
The two regression lines are and . The coefficient of correlation between and is
A. B. C. D.mediumAsked in NIMCET 2011View solution āŗ - Q11.
If the mean of the first natural numbers is , then is equal to
A. B. C. D.easyAsked in NIMCET 2011View solution āŗ - Q12.
Standard deviation for the following distribution is Size of item: 6, 7, 8, 9, 10, 11, 12 Frequency: 3, 6, 9, 13, 8, 5, 4
A. 1.607B. 9.0C. 5.0D. 1.88mediumAsked in NIMCET 2020View solution āŗ - Q13.
The standard deviation of 20 numbers is 30. If each of the numbers is increased by 4, then the new standard deviation will be
A. 24B. 34C. 30D. 20easyAsked in NIMCET 2021View solution āŗ - Q14.
If a variable takes the values with frequencies , then the AM is
A. 50B. 25C. D. 51mediumAsked in NIMCET 2021View solution āŗ - Q15.
The 10th and 50th percentiles of the observations 32, 49, 23, 29, 118 respectively are
A. 21, 32B. 23, 32C. 23, 33D. 22, 31easyAsked in NIMCET 2022View solution āŗ - Q16.
The first three moments of a distribution about 2 are 1, 16 and respectively. The mean and variance of the distribution are
A. (2, 16)B. (2, 15)C. (3, 15)D. (1, 16)mediumAsked in NIMCET 2022View solution āŗ - Q17.
The mean of 25 observations was found to be 38. It was later discovered that 23 and 38 were misread as 25 and 36, then the mean is
A. 32B. 36C. 38D. 42easyAsked in NIMCET 2022View solution āŗ - Q18.
The mean deviation from the mean of the AP is:
A. B. C. D.mediumAsked in NIMCET 2014View solution āŗ - Q19.
If the mean deviation of the numbers from their mean is 255, then the value of is
A. 20.0B. 10.1C. 20.2D. 10.0mediumAsked in NIMCET 2015View solution āŗ - Q20.
If the mean deviation of the numbers from their mean is 255, then d is equal to
A. 10.1B. 10.2C. 10.02D. 10.4mediumAsked in NIMCET 2019View solution āŗ