- A20-30
- B0-10
- C40-50
- D25-35
Step-by-Step Solution
We add a class of the same size just before the first class: 30 - 10 = 20, so the class is 20-30 with frequency 0.
Answer: A) 20-30
The first class of a distribution is 30-40 with class size 10. Which imaginary class is added before it (with zero frequency) to close the polygon?
Class 9Frequency PolygonsStatistics and Probability
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