NBT Quantitative Literacy Data and Graphs — Questions and Answers
Question 1: A bar graph shows monthly rainfall in Cape Town: Jan 15mm, Feb 17mm, Jun 93mm, Jul 82mm. Which month had the highest rainfall?
- January
- June (Correct answer)
- February
- July
Correct answer: June
June recorded 93mm, the largest value shown, so it is the wettest month in the data.
Question 2: A pie chart shows a household budget: Rent 40%, Food 25%, Transport 20%, Other 15%. If the total monthly income is R12 000, how much is spent on rent?
- R3 000
- R6 000
- R4 800 (Correct answer)
- R2 400
Correct answer: R4 800
Rent is 40% of R12 000. 0.40 x 12 000 = R4 800.
Question 3: A table lists test scores: 60, 72, 72, 80, 96. What is the mode of these scores?
- 96
- 72 (Correct answer)
- 60
- 80
Correct answer: 72
The mode is the most frequent value. 72 appears twice while all others appear once, so the mode is 72.
Question 4: A line graph shows a learner's marks rising from 45% in Term 1 to 63% in Term 4. What is the total percentage-point increase?
- 63 points
- 28 points
- 18 points (Correct answer)
- 8 points
Correct answer: 18 points
The increase is 63% - 45% = 18 percentage points.
Question 5: A dataset of five values is 4, 6, 6, 8, 11. What is the mean (average)?
- 8
- 11
- 6
- 7 (Correct answer)
Correct answer: 7
Sum = 4+6+6+8+11 = 35. Mean = 35 / 5 = 7.
Question 6: A graph's vertical axis is labelled 'Number of learners (thousands)' and a bar reaches 3.5. How many learners does this represent?
- 350
- 3 500 (Correct answer)
- 35 000
- 35
Correct answer: 3 500
The axis is in thousands, so a value of 3.5 means 3.5 x 1 000 = 3 500 learners.
Question 7: Two data sets have the same mean but Set A's values are tightly clustered while Set B's are widely spread. Which set has the greater range?
- They are equal
- Set B (Correct answer)
- Set A
- Range cannot relate to spread
Correct answer: Set B
Range measures spread (highest minus lowest). The more widely spread Set B has the larger range.
Question 8: A survey of 200 students shows 30% prefer online classes. How many students prefer online classes?
- 30
- 70
- 60 (Correct answer)
- 200
Correct answer: 60
30% of 200 = 0.30 x 200 = 60 students.
NBT Quantitative Literacy Data and Graphs
A bar graph shows monthly rainfall in Cape Town: Jan 15mm, Feb 17mm, Jun 93mm, Jul 82mm.
Which month had the highest rainfall?