A histogram of exam marks has classes 0-20, 20-40, 40-60, 60-80, 80-100. The frequencies form an arithmetic progression and their sum is 40. The class 0-20 has frequency 4 and the class 80-100 has frequency 12. What is the frequency of the middle class 40-60?

Question

Accepted Answer

8. An AP with first term 4 and last term 12 has middle (third) term = (4 + 12)/2 = 8. Check: terms 4,6,8,10,12 sum to 40, consistent.

A histogram of exam marks has classes 0-20, 20-40, 40-60, 60-80, 80-100.
The frequencies form an arithmetic progression and their sum is 40.
The class 0-20 has frequency 4 and the class 80-100 has frequency 12.
What is the frequency of the middle class 40-60?

Step-by-Step Solution

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More Class 9 Bar Graphs and Histograms practice

A histogram of exam marks has classes 0-20, 20-40, 40-60, 60-80, 80-100.The frequencies form an arithmetic progression and their sum is 40.The class 0-20 has frequency 4 and the class 80-100 has frequency 12.What is the frequency of the middle class 40-60?

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 9 Bar Graphs and Histograms practice

A histogram of exam marks has classes 0-20, 20-40, 40-60, 60-80, 80-100.
The frequencies form an arithmetic progression and their sum is 40.
The class 0-20 has frequency 4 and the class 80-100 has frequency 12.
What is the frequency of the middle class 40-60?