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The following frequency distribution table shows the distances travelled by some rickshaws in a day. Observe the table and answer the following questions
Class (Daily distance travelled in km) 
Continuous Classes 
Frequency (no.of. rickshaws) 
Cumulative frequency less than type 
60 – 64  59.5 – 64.5  10  10 
65 – 69  64.5 – 69.5  34  10 + 34 = 44 
70 – 74  69.5 – 74.5  58  44 + 58 = 102 
75 – 79  74.5 – 79.5  82  102 + 82 = 184 
80 – 84  79.5 – 84.5  10  184 + 10 = 194 
85 – 89  84.5 – 89.5  6  194 + 6 = 200 
 Which is the modal class? Why?
 Which is the median class and why?
 Write the cumulative frequency (C.F) of the class preceding the median class.
 What is the class interval (h) to calculate median?
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Solution
1. Model class is the class that contains highest frequency i.e.
highest frequency = 82
highest frequency class = 75 – 79
2. Median class is the class that contain `(N/2)^(th)` term. Where N is total frequency.
N = 200
`(N/2) = 100`
`(N/2)^(th)` term will lie in (70 – 74) class
3. Cumulative frequency = 44
4. Median class = 70 – 74
OR
69.5 – 74.5 ......(Continuous)
h = U.l. – L.l.
= 74.5 – 69.5 = 5
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