Same chapter3 marksDifficulty: Medium
Explain the term cumulative frequency and state how the cumulative frequency of a class is obtained.
Graphical Representation
3 marksDifficulty: Medium
Why must class intervals be converted to their exclusive form before a histogram is drawn?
Original Khojo Papers practice question — not from a past board paper.
Answer
A histogram represents frequency by area and its bars must touch, which is only possible if the upper boundary of one class is the lower boundary of the next. Inclusive intervals such as 10–19 and 20–29 leave a gap, so they are adjusted to 9.5–19.5 and 19.5–29.5 first.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The adjustment factor is half the difference between the upper limit of one class and the lower limit of the next.
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