The document RD Sharma Solutions - Chapter 23 - Data Handling-I (Part - 2), Class 8, Maths Class 8 Notes | EduRev is a part of the Class 8 Course RD Sharma Solutions for Class 8 Mathematics.

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**PAGE NO 23.14:**

**Question 1:**

**The marks obtained by 40 students of class VIII in an examination are given below: 16, 17, 18, 3, 7, 23, 18, 13, 10, 21, 7, 1, 13, 21, 13, 15, 19, 24, 16, 3, 23, 5, 12, 18, 8, 12, 6, 8, 16, 5, 3, 5, 0, 7, 9, 12, 20, 10, 2, 23. Divide the data into five groups, namely 0âˆ’5, 5âˆ’10, 10âˆ’15, 15âˆ’20 and 20âˆ’25 and prepare a grouped frequency table.**

**ANSWER:**

The frequency table for the marks of 40 students of class VIII in an examination is given below:

Range of Marks | Tally Marks | Frequency |

0âˆ’5 | |||| | 9 |

5âˆ’10 | |||| | 9 |

10âˆ’15 | || | 7 |

15âˆ’20 | |||| | 9 |

20âˆ’25 | | | 6 |

**Question 2:**

**The marks scored by 20 students in a test are given below: 54, 42, 68, 56, 62, 71, 78, 51, 72, 53, 44, 58, 47, 64, 41, 57, 89, 53, 84, 57. Complete the following frequency table:**

(Marks in class intervals) | Tally marks | Frequency (no. of children) |

40âˆ’50 | ||

50âˆ’60 | ||

60âˆ’70 | ||

70âˆ’80 | ||

80âˆ’90 |

**What is the class interval in which the greatest frequency occurs?**

**ANSWER:**

The frequency table can be completed as follows:

Marks | Tally Marks | Frequency |

40âˆ’50 | |||| | 4 |

50âˆ’60 | ||| | 8 |

60âˆ’70 | ||| | 3 |

70âˆ’80 | ||| | 3 |

80âˆ’90 | || | 2 |

The class interval with the greatest frequency (8) is 50âˆ’60.

**Question 3:**

**The following is the distribution of weights (in kg) of 52 persons:**

Weight in kg | Persons |

30âˆ’40 | 10 |

40âˆ’50 | 15 |

50âˆ’60 | 17 |

60âˆ’70 | 6 |

70âˆ’80 | 4 |

**(i) What is the lower limit of class 50âˆ’60? (ii) Find the class marks of the classes 40âˆ’50, 50âˆ’60. (iii) What is the class size?**

**ANSWER:**

(i) The lower limit of the class 50âˆ’60 is 50.

(ii) Class mark for the class 40âˆ’50:

= 90/2 = 45

Again, class mark for the class 50âˆ’60:

= 110/2 = 55

(iii) Here the class size is 40âˆ’30, i.e. 10.

**Question 4:**

**Construct a frequency table for the following weights (in gm) of 35 mangoes using the equal class intervals, one of them is 40âˆ’50 (45 not included): 30, 40, 45, 32, 43, 50, 55, 62, 70, 70, 61, 62, 53, 52, 50, 42, 35, 37, 53, 55, 65, 70, 73, 74, 45, 46, 58, 59, 60, 62, 74, 34, 35, 70, 68. (i) What is the class mark of the class interval 40âˆ’45? (ii) What is the range of the above weights? (iii) How many classes are there?**

**ANSWER:**

The frequency table for the given weights (in gm) of 35 mangoes is given below:

Weight | Tally Marks | Frequency |

30âˆ’40 | | | 6 |

40âˆ’50 | | | 6 |

50âˆ’60 | |||| | 9 |

60âˆ’70 | || | 7 |

70âˆ’80 | || | 7 |

(i) Class mark for the class interval 40âˆ’45:

Class mark = = 85/2 = 42.5

(ii) Range of the above weights:

Range = Highest valueâˆ’Lowest value

= 74âˆ’30

= 44

(iii) There are 5 classes (30âˆ’40, 40âˆ’50, 50âˆ’60, 60âˆ’70, 70âˆ’80).

**Question 5:**

**Construct a frequency table with classâˆ’intervals 0âˆ’5 (5 not included) of the following marks obtained by a group of 30 students in an examination. 0, 5, 7, 10, 12, 15, 20, 22, 25, 27, 8, 11, 17, 3, 6, 9, 17, 19, 21, 29, 31, 35, 37, 40, 42,45, 49, 4, 50, 16.**

**ANSWER:**

The frequency table with class intervals 0âˆ’5,5âˆ’10,10âˆ’15,...,50âˆ’55 is given below:

Marks | Tally Marks | Frequency |

0âˆ’5 | ||| | 3 |

5âˆ’10 | 5 | |

10âˆ’15 | ||| | 3 |

15âˆ’20 | 5 | |

20âˆ’25 | ||| | 3 |

25âˆ’30 | ||| | 3 |

30âˆ’35 | | | 1 |

35âˆ’40 | || | 2 |

40âˆ’45 | || | 2 |

45âˆ’50 | || | 2 |

50âˆ’55 | | | 1 |

**Question 6:**

**The marks scored by 40 students of class VIII 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.**

**ANSWER:**

The frequency table of the marks scored by 40 students of class VIII in mathematics is given below:

Mark | Tally Marks | Frequency |

20âˆ’30 | | | 1 |

30âˆ’40 | ||| | 3 |

40âˆ’50 | 5 | |

50âˆ’60 | ||| | 8 |

60âˆ’70 | ||| | 8 |

70âˆ’80 | |||| | 9 |

80âˆ’90 | |||| | 4 |

90âˆ’100 | || | 2 |

**PAGE NO 23.15:**

**Question 7:**

**The heights (in cm) of 30 students of class VIII 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 160âˆ’164 as one of the class intervals.**

**ANSWER:**

The frequency table is given below:

Height | Tally Marks | Frequency |

145âˆ’149 | |||| | 4 |

150âˆ’154 | |||| | 9 |

155âˆ’159 | || | 12 |

160âˆ’164 | 5 |

**Question 8:**

**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 with class size 10.**

**ANSWER:**

The frequency table of the monthly wages of 30 workers in a factory is given below:

Wage | Tally Marks | Frequency |

800âˆ’810 | ||| | 3 |

810âˆ’820 | || | 2 |

820âˆ’830 | | | 1 |

830âˆ’840 | ||| | 8 |

840âˆ’850 | 5 | |

850âˆ’860 | | | 1 |

860âˆ’870 | ||| | 3 |

870âˆ’880 | | | 1 |

880âˆ’890 | | | 1 |

890âˆ’900 | 5 |

**Question 9:**

**Construct a frequency table with equal class intervals from the following data on the monthly wages (in rupees) of 28 labourers working in a factory, taking one of the class intervals as 210âˆ’230 (230 not included): 220, 268, 258, 242, 210, 268, 272, 242, 311, 290, 300, 320, 319, 304, 302, 318, 306, 292, 254, 278, 210, 240, 280, 316, 306, 215, 256, 236.**

**ANSWER:**

The frequency table of the monthly wages of 28 labourers working in a factory is given below:

Wage | Tally Marks | Frequency |

210âˆ’230 | |||| | 4 |

230âˆ’250 | |||| | 4 |

250âˆ’270 | 5 | |

270âˆ’290 | ||| | 3 |

290âˆ’310 | || | 7 |

310âˆ’330 | 5 |

**Question 10:**

**The daily minimum temperatures in degrees Celsius recorded in a certain Arctic region are as follows: âˆ’12.5,âˆ’10.8,âˆ’18.6,âˆ’8.4,âˆ’10.8,âˆ’4.2,âˆ’4.8,âˆ’6.7,âˆ’13.2,âˆ’11.8,âˆ’2.3, 1.2, 2.6, 0,âˆ’2.4, 0, 3.2, 2.7, 3.4, 0,âˆ’2.4,âˆ’2.4, 0, 3.2, 2.7, 3.4, 0,âˆ’2.4,âˆ’5.8,âˆ’8.9,âˆ’14.6,âˆ’12.3,âˆ’11.5,âˆ’7.8,âˆ’2.9 Represent them as frequency distribution table takingâˆ’19.9 toâˆ’15 as the first class interval.**

**ANSWER:**

The frequency table of the daily minimum temperatures is given below:

Temperature | Tally Marks | Frequency |

âˆ’19.9 to âˆ’15 | | | 1 |

âˆ’14.9 to âˆ’10 | ||| | 8 |

âˆ’9.9 to âˆ’5 | 5 | |

âˆ’4.9 to 0 | ||| | 13 |

0.1 to 5 | ||| | 8 |