Practise calculating averages and interpreting data with these MCQs for Class 8 Maths, Ganita Prakash Part 2, Chapter 5: Tales by Dots and Lines. Answers and explanations show how to find means and medians, correct recorded values, work with spreadsheet cells and read changes in data. Examples involving temperatures, space launches, rainfall, daily activities and prices also help you decide which conclusions the available information supports.
Class 8 Maths Ganita Prakash Part 2 Chapter 5 MCQs with Answers
Set 1: Mean as a Balance Point MCQs (Questions 1–5)
Q2. The data are 10, 10, 11, and 17. Which value balances the data so that the total distances below and above it are equal?
[A]. 12
[B]. 11
[C]. 13.5
[D]. 10
Q3. A collection has a mean of 12. A new value equal to 12 is included. What happens to the mean?
[A]. It remains 12
[B]. It becomes 24
[C]. It becomes less than 12
[D]. It becomes greater than 12
Q4. A collection has a mean of 9. Which pair of values can be included without changing its mean?
[A]. 7 and 11
[B]. 9 and 12
[C]. 7 and 9
[D]. 10 and 12
Q5. The average height of 24 students is recorded as 150.2 cm while they are wearing shoes. Each pair of shoes adds 1 cm to the height. What is the correct average height without shoes?
[A]. 151.2 cm
[B]. 149.2 cm
[C]. 150.2 cm
[D]. 126.2 cm
Set 2: Mean Calculations and Median from Frequencies MCQs (Questions 6–10)
Q6. The mean of a collection of n numbers is a. If every number is multiplied by 5, which expression always gives the new mean?
[A]. a + 5
[B]. 5a/n
[C]. 5a
[D]. a/5
Q7. Ten wrestlers have a mean weight of 39.2 kg. Nine weights are 42, 40, 39, 33, 48, 38, 42, 35, and 32 kg. What is the missing weight?
[A]. 43 kg
[B]. 42 kg
[C]. 39.2 kg
[D]. 49 kg
Q8. The recorded average coconut harvest from 15 trees is 25.6 coconuts per tree. One tree’s count was recorded as 3 more than its actual count. What is the correct average?
[A]. 25.6
[B]. 22.6
[C]. 25.4
[D]. 25.8
Q9. Family sizes 3, 4, 5, 6, 7, 8, 9, and 10 occur with frequencies 3, 11, 9, 7, 3, 1, 1, and 1, respectively. What is the mean family size, rounded to two decimal places?
[A]. 6.50
[B]. 5.00
[C]. 4.75
[D]. 5.22
Q10. Family sizes 3, 4, 5, 6, 7, 8, 9, and 10 occur with frequencies 3, 11, 9, 7, 3, 1, 1, and 1, respectively. What is the median family size?
[A]. 5
[B]. 5.5
[C]. 4
[D]. 6.5
Set 3: Spreadsheets, Mean and Median MCQs (Questions 11–15)
Q11. In a spreadsheet, Mathematics marks are in column E, and Farooq’s details are in row 5. What is the cell address of Farooq’s Mathematics mark?
[A]. E5
[B]. E4
[C]. 5E
[D]. D5
Q12. Nagesh’s marks in six subjects are entered in cells B3 to G3. Which formula gives his total marks?
[A]. =AVERAGE(B3:G3)
[B]. =AVERAGE(B3:B8)
[C]. =SUM(B3:B8)
[D]. =SUM(B3:G3)
Q13. What is the mean of the natural numbers from 1 to 50?
[A]. 50
[B]. 25.5
[C]. 1,275
[D]. 25
Q14. What is the median of 8, 10, 19, 23, 26, 34, 40, 41, 41, 48, 51, 55, 70, 84, 91, and 92?
[A]. 44.5
[B]. 40
[C]. 41
[D]. 48
Q15. The mean of 8, 13, 10, 4, 5, 20, y, and 10 is 10.375. What is y?
[A]. 10.375
[B]. 12
[C]. 13
[D]. 10
Set 4: Averages, Line Graphs and Temperature Range MCQs (Questions 16–20)
Q16. A collection of 15 values has a mean of 134. What is the sum of all its values?
[A]. 149
[B]. 1,340
[C]. 119
[D]. 2,010
Q17. The ordered data are 4, 7, 8, 12, and 14. If 11 is included, what is the new median?
[A]. 10
[B]. 11
[C]. 9.5
[D]. 8
Q18. A group’s mean weight is 65.3 kg and its median weight is 67 kg. Next month, one person loses 2 kg and two others gain 1 kg each. Everyone else’s weight is unchanged. Which statement must be true?
[A]. The mean stays 65.3 kg and the median must stay 67 kg
[B]. The mean decreases by 2 kg
[C]. The mean stays 65.3 kg; the new median cannot be determined from this information
[D]. The mean and median both increase
Q19. Which graph is especially suitable for showing how monthly maximum temperatures change through a year?
[A]. A dot plot with the months omitted
[B]. A line graph
[C]. A map showing food preferences
[D]. An activity strip showing one day
Q20. The monthly maximum temperatures in Punjab range from about 19°C to 38°C. In Kerala, they range from about 29°C to 33°C. Which statement is correct?
[A]. Punjab’s range is 4°C
[B]. Punjab’s range is about 19°C, which is greater than Kerala’s range of 4°C
[C]. Kerala’s range is 19°C
[D]. Both ranges are 4°C
Set 5: Line Graphs and Data Comparisons MCQs (Questions 21–25)
Q21. The worldwide number of objects launched into space is approximately 2,900 in 2023 and 2,800 in 2024. What change do these figures show?
[A]. A decrease of about 100 objects
[B]. An increase of about 100 objects
[C]. No change
[D]. A decrease of about 1,000 objects
Q22. A space-launch graph shows separate counts for the USA, China, and Russia, along with the worldwide count. In one year, the three countries’ counts together are less than the worldwide count. What follows?
[A]. All countries launched equal numbers
[B]. At least one other country contributed to the worldwide count
[C]. Every unlisted country launched no objects
[D]. The worldwide total must be incorrect
Q23. On the same line graph with uniform scales, two rising line segments each cover one year. The first segment is steeper than the second. What does this show?
[A]. The increase is greater during the first year
[B]. The quantity decreases in the first year
[C]. Both increases must be equal
[D]. The increase is greater during the second year
Q24. The average numbers of visitors and purchasers at a shop are: Monday (16, 10), Tuesday (19, 8), Friday (20, 12), and Sunday (35, 26). On which of these days is the difference between visitors and purchasers greatest?
[A]. Friday
[B]. Tuesday
[C]. Monday
[D]. Sunday
Q25. Mangaluru’s average numbers of rainy days are June: 24.1, July: 27.7, August: 24.5, and September: 14.0. Which month has the highest value, and what is that value rounded to the nearest whole day?
[A]. August, 25 days
[B]. September, 14 days
[C]. June, 24 days
[D]. July, 28 days
Set 6: Everyday Data and Valid Conclusions MCQs (Questions 26–30)
Q26. A rice–wheat preference index ranges from −100 to +100, with positive values favouring rice. The index is based on the difference in per-person consumption of the two grains. What does +100 indicate?
[A]. Wheat is preferred over rice
[B]. The strongest rice preference on this scale
[C]. Everyone eats only rice
[D]. Rice and wheat are equally preferred
Q27. Manoj’s activity strip has one box for each 30-minute interval. His school day lasts from 9:30 am to 4:30 pm, including breaks. How many boxes represent this time?
[A]. 21
[B]. 7
[C]. 12
[D]. 14
Q28. A graph shows the average time a group of children spends on hobbies and games. Can this average alone tell us the exact time spent by every child?
[A]. Yes; every child spends exactly the average time
[B]. Yes; every child spends at most the average time
[C]. No; different individual times can have the same average
[D]. Yes; every child spends at least the average time
Q29. A graph shows the percentage of households using electricity as their primary lighting source. Can this graph alone establish that there were no power cuts in a particular year?
[A]. No; it proves that every household had power cuts
[B]. Yes, whenever electricity is used by a majority
[C]. Yes, whenever kerosene use decreases
[D]. No; it does not show the frequency or duration of power cuts
Q30. The January prices of salt in 2016 and 2025 are: Assam ₹6 and ₹12.35; Mizoram ₹20 and ₹29.80; Uttar Pradesh ₹16.15 and ₹24.81; West Bengal ₹9.47 and ₹23.99. Which of these states has the greatest increase in rupees?
[A]. Uttar Pradesh
[B]. Mizoram
[C]. Assam
[D]. West Bengal
Check Calculations and Conclusions Separately
For mean questions, write down the total and the number of values before making a correction. For medians, arrange the data and identify the middle positions. When reading graphs, check the scale, units and time interval. Finally, separate what the data actually show from claims they cannot establish, such as every person’s individual value.
