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Question
The following histogram shows the frequency distribution of teaching experiences of 30 teachers in various schools:
- What is the class width?
- How many teachers are having the maximum teaching experience and how many have the least teaching experience?
- How many teachers have teaching experience of 10 to 20 years?
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Solution
- In the histogram, we see that the class width is 5.
- By the histogram, it is clear that two teachers have the maximum teaching experience, i.e. 15 – 20 years, and five teachers have the least teaching experience, i.e. 0 – 5 years.
- The number of teachers having experience from 10 to 20 years is 7 + 2, i.e. 9.
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