CA Foundation · Quantitative Aptitude · Statistical Description of Data
A frequency distribution has classes of equal width 15, and the lowest class begins at 10. The first class is 10–25 under the exclusive method. If the highest observation in the data is 88, what is the least number of classes needed to cover all observations?
At least 6 classes are needed. Starting at 10 with width 15, the classes end at 25, 40, 55, 70, 85 and 100. The value 88 exceeds 85, so a sixth class, 85–100, is required to include it.
- A5
- B6Correct
- C7
- D4
Explanation
Classes: 10–25, 25–40, 40–55, 55–70, 70–85, 85–100. The value 88 falls in 85–100, which is the sixth class. Five classes end at 85 and would leave out 88, so 5 is wrong.
Did you get it right without looking?
One question tells you little. A timed set on Statistical Description of Data shows your real accuracy, how long you take and where you lose marks.
More Statistical Description of Data questions
- Marks of 80 students are tabulated with class intervals 0-10, 10-20, 20-30, 30-40 and 40-50 using the exclusive method. The frequencies are …
- Using the 'less than' ogive data of a Nagpur firm's 80 workers: less than 10: 8; less than 20: 24; less than 30: 52; less than 40: 72; less …
- A histogram is drawn for a continuous frequency distribution with unequal class widths. To make the heights of the rectangles correctly repr…
- A distribution of 100 observations has class intervals 0–20, 20–40, 40–60, 60–80, 80–100. The relative frequencies are 0.10, 0.25, 0.30, 0.2…
- A company in Surat wants quick opinions from customers about a new product. It sends a questionnaire by post, and customers fill it in and m…
- A researcher wants to show how the total monthly expenditure of a company is divided among five heads such as salaries, rent and marketing, …