Ex-22.1 (Part - 2), Tabular Representation Of Statistical Data, Class 9, Maths RD Sharma Solutions | RD Sharma Solutions for Class 9 Mathematics PDF Download

Q13. Write the class size and class limits in each of the following:

(i) 104,114,124,134,144,154 and 164.

(ii) 47,52,57,62,67,72,78,82,87,92,97,102.

(iii) 12.5, 17.5, 22.5, 27.5, 32.5, 37.5, 42.5, 47.5.

Solution 13:

 (1) 104,114,124,134,144,154 and 164.

Class size = 114-104 = 10

Class mark	Lower class limit	Upper class limit	Class limit
104			99-109
114			109-119
124	119	129	119-129
134	129	139	129-139
144	139	149	139-149
154	149	159	149-159
164	159	169	159-169

(2)  47,52,57,62,67,72,78,82,87,92,97,102.

Class size = 52-47 = 5

Class mark	Lower class limit	Upper class limit	Class limit
47			44.5-49.5
52	49.5	54.5	49.5-54.5
57	54.5	59.5	54.5-59.5
62	59.5	64.5	59.5-64.5
67	64.5	69.5	64.5-69.5
72	69.5	74.5	69.5-74.5
77	74.5	79.5	74.5-79.5
82	79.5	84.5	79.5-84.5
87	84.5	89.5	84.5-89.5
92	89.5	94.5	89.5-94.5
97	94.5	99.5	94.5-99.5
102	99.5	104.5	9.5-104.5

(3)12.5, 17.5, 22.5, 27.5, 32.5, 37.5, 42.5, 47.5.

Class size = 17.5-12.5 = 5

Q14. Following data gives the number of children in 40 families:

1,2,6,5,1,5,1,3,2,6,2,3,4,2,0,0,4,4,3,2,2,0,0,1,2,2,4,3,2,1,0,5,1,2,4,3,4,1,6,2,2.  

Represent it in the form of a frequency distribution.

Solution 14:

Q15. Marks scored by 40 students of class IX in mathematics are given below:

81,55,68,79,85,43,29,68,54,73,47,35,72,64,95,44,50,77,64,35,79,52,45,54,70,83,62,64,72,92,84,76,63,43,54,38,73,68,52,54.

 Prepare a frequency distribution with class size of 10 marks.

Solution 15:

Q16. Heights (in cm) of 30 students of class IX are given below:

155,158,154,158,160,148,149,150,153,159,161,148,157,153,157,162,159, 151,  154,  156 , 152 , 156 , 160,  152,  147,  155,  163,  155 , 157 , 153.

Prepare a frequency distribution table with 160-164 as one of the class intervals.

Solution 16:

Q17. The monthly wages of 30 workers in a factory are given below:

830, 835, 890, 810, 835, 836, 869, 845, 898, 890, 820, 860, 832, 833, 855,        845, 804, 808, 812, 840, 885, 835, 836, 878, 840, 868, 890, 806, 840, 890.

Represent the data in the form of a frequency distribution table with class size 10.

Solution 17:

Q18. The daily maximum temperatures (in degree Celsius) recorded in a certain city during the month of November are as follows:

25.8,24.5,25.6,20.7,21.8,20.5,20.6,20.9,22.3,22.7,23.1,22.8,22.9,21.7,21.3,20.5,20.9,23.1,22.4, 21.5,22.7,22.8,22.0,23.9,24.7,22.8,23.8,24.6,23.9,21.1.

Represent the data in the form of a frequency distribution table with class size 1 10CC.

Solution 18:

Q19. Construct a frequency table with equal class intervals from the following data on the monthly wages (in rupees) of 28 laborers working in a factory, taking one of the class intervals as 210-230(230 not included).

220,268,258,242,210,268,272,242,311,290,300,320,319,304,302,218,306,292,254,278,210,240,280,316,306,215,256,236.   

Solution 19:

Q20 The daily minimum temperatures in degree Celsius recorded in a certain arctic region are as follows:

-12.5,-10.8,-18.6,-8.4-10.8,-4.2,-4.8,-6.7,-13.2,-11.8,-2.3,-1.2,

-2.6,0,2.4,0,3.2,2.7,3.4,0,-2.4,-2.4,0,3.2,2.7,3.4,0,-2.4,-5.8,-8.9,-14.6,-12.3,

-11.5,-7.8,-2.9.

Represent them as frequency distribution table taking -19.9 to -15 as the first class interval.

Solution 20:

Since first class interval is -19.9 to -15, frequency distribution with lower limit included and upper limit excluded is:

Q21. The blood groups of 30 students of class VIII are recorded as follows:

 A,B,O,O,AB,O,A,O,B,A,O,B,A,O,O,A,AB,O,A,A,O,O,AB,B,A,O,B,A,B,O

 Represent this data in the form of a frequency distribution table .Find out which is the most common and which is the most rarest blood group among these students.

Solution 21:

Here 9 students have blood group A,6 as B,3 as AB and 12 as O

So the table representing the data is as follows:

As 12 students have their blood group O and 3 students have their blood group as AB. Therefore the most common blood group is O and the rarest blood group is AB.

Q22. Three coins were tossed 30 times. Each time the number of heads occurring was noted down as follows:

0, 1, 2, 2, 1, 2, 3, 1, 3, 0

1, 3, 1, 1, 2, 2, 0, 1, 2, 1

3, 0, 1, 1, 2, 3, 2, 2, 0

Prepare a frequency distribution table for the data given above.

Solution 22:

By observing the data given above , the following frequency table can be constructed:

Q23. Thirty children were asked about the number of hours they watched TV programes in the previous week. The results were found as follows:

1, 6, 2, 3, 5, 12, 5, 8, 4, 8

10, 3, 4, 12, 2, 8, 15, 1, 17, 6

3, 2, 8, 5, 9, 6, 8, 7, 14, 2.

(i)Make a frequency distribution table for this data , taking class width 5 and one of the class intervals as 5-10.

(ii)How many children watched television for 15 or more hours a week.

Solution 23:

(i) Class intervals will be 0-5, 5-10, 10-15 …

The grouped frequency distribution table is as follows:

(ii) The number of children who watched TV for 15 or more hours a week is 2(i.e number of children in class interval 15-20).