Practice Set 6.2

- The following table shows classification of number of workers and the number of hours…
- The frequency distribution table shows the number of mango trees in a grove and their…
- The following table shows the classification of number of vehicles and their speeds on…
- The production of electric bulbs in different factories is shown in the following…

###### Practice Set 6.2

Question 1.

The following table shows classification of number of workers and the number of hours they work in a software company. Find the median of the number of hours they work.

Answer:

⇒ N = 1000

⇒ 500 Lies in class 10-12

⇒ Median class 10-12

L = lower limit of median class = 10

N = sum of frequencies = 1000

h = class interval of median class = 2

f = frequency of median class = 500

cf = cumulative frequency of class preceding median class = 150

⇒ Median

⇒ Median

⇒ Median = 11.4

Question 2.

The frequency distribution table shows the number of mango trees in a grove and their yield of mangoes. Find the median of data.

Answer:

⇒ N = 250

⇒ 125 Lies in class 100-150

⇒ Median class 100-150

L = lower limit of median class = 100

N = sum of frequencies = 250

h = class interval of median class = 50

f = frequency of median class = 30

cf = cumulative frequency of class preceding median class = 33

⇒ Median

⇒ Median =

⇒ Median = 253.33

Question 3.

The following table shows the classification of number of vehicles and their speeds on Mumbai-Pune express way. Find the median of the data.

Answer:

The class is discontinuous between 69-74 and 75-79

Converting the to continuous class

⇒ N = 200

⇒ 100 Lies in class 74.5-79.5

⇒ Median class 74.5-79.5

L = lower limit of median class = 74.5

N = sum of frequencies = 200

h = class interval of median class = 5

f = frequency of median class = 85

cf = cumulative frequency of class preceding median class = 99

⇒ Median

⇒ Median

⇒ Median = 74.558

Question 4.

The production of electric bulbs in different factories is shown in the following table. Find the median of the productions.

Answer:

⇒ N = 105

⇒ 52.5 Lies in class 50-60

⇒ Median class 50-60

L = lower limit of median class = 50

N = sum of frequencies = 105

h = class interval of median class = 10

f = frequency of median class = 20

cf = cumulative frequency of class preceding median class = 47

⇒ Median

⇒ Median

⇒ Median = 52.75

⇒ In thousands = 52.75× 1000 = 52750 lamps