Content text 03-Statistics (Part-2)(1).pdf
EXERCISE A. Very Short Answer Type Questions Q.1 The class marks of distribution are : 6, 10, 14, 18, 22, 26,30 Find the class size and the class interval. Q.2 The class marks of distribution are : 47, 52, 57, 62, 67, 72, 77, 82, 87, 92, 97, 102. Determine the class size, the class limits and the true class limits. Q.3 Find the range of the following array of data : 70, 65, 71,36, 55, 61, 62, 41, 40, 39, 35. Q.4 Draw the ogive of the following distribution table: Class interval 0-10 10-20 20-30 30-40 40-50 50-60 Frequency 10 5 8 6 6 4 Q.5 The weights (in kilograms) of 25 students are given as follows : 35, 38, 36, 37, 38, 35, 37, 36, 35, 38, 36, 36, 37, 37, 35, 38, 36, 35, 36, 37, 37, 38, 36, 38, 37. Complete the following frequency table: Weights 35 36 37 38 Frequency – – – – Q.6 The marks scored by 55 students in a test are given below : Marks No. of students 0-5 2 5-10 6 10-15 13 15-20 17 20-25 11 25-30 4 30-35 2 Prepare a cumulative frequency table. Q.7 Find the mean of all factors of 10. Q.8 Find the mean of first 10 even natural numbers. Q.9 Following are weights (in kg) of 10 new born babies in a hospital on a particular day : 3.4, 3.6, 4.2, 4.5, 3.9, 4.1, 3.8, 4.5, 4.4, 3.6. Find the mean X . Q.10 Calculate the mean for the following distribution: x : 5 6 7 8 9 f : 4 8 14 11 3 Q.11 Find the mean of the following distribution: x : 10 12 20 25 35 f : 3 10 15 7 5 Q.12 Find out the mode of the following marks obtained by 15 students in a class: Marks : 4, 6, 5, 7, 9, 8, 10, 4, 7, 6, 5, 9, 8, 7, 7 Q.13 Find the mode for the following series: 7.5, 7.3, 7.2, 7.2, 7.4, 7.7, 7.7, 7.5, 7.3, 7.2, 7.6, 7.2 Apply Direct method to find arithmetic mean in each of the following : Q.14 Class- interval 0–6 6–12 12–18 18–24 24–30 Frequency 7 5 10 12 6 Q.15 Class- interval 0–10 10–20 20–30 30–40 40–50 Frequency 8 10 9 12 11 Q.16 Class- interval 100–120 120–140 140–160 160–180 180–200 Frequency 10 20 30 15 5 Q.17 Calculate the mode for the following frequency distribution. Class- interval 0–4 4–8 8–12 12–16 Frequency 4 8 5 6
Q.18 Find out the mode for the following data showing frequency with which profits are made: Profits (in '000 rupees) Frequency 3 – 4 83 4 – 5 27 5 – 6 25 6 – 7 50 7 – 8 75 8 – 9 38 9 –10 18 Q.19 Find the mode of the following series : Wages (Rs.) No. of persons 0 – 25 10 25 – 50 30 50 – 75 40 75 – 100 25 100 – 125 20 125 – above 15 Q.20 Compute the mode of the following distribution x f 0 – 5 20 5 – 10 24 10 – 15 32 15 – 20 28 20 – 25 20 25 – 30 16 30 – 35 17 35 – 40 10 40 – 45 18 Q.21 Compute the mode for the following data : Class Frequency 10 – 20 24 20 – 30 42 30 – 40 56 40 – 50 66 50 – 60 108 60 – 70 130 70 – 80 154 80 – 90 140 B. Short Answer Type Questions Q.22 A cumulative frequency distribution table is given. Convert this into a frequency distribution table. Marks below 45 below 60 below 75 below 90 Number of student 0 8 23 48 Q.23 Draw a frequency table for the following data: C.I. C.F. 111-120 6 121-130 11 131-140 16 141-150 20 151-160 27 161-170 36 171-180 42 181-190 45 191-200 50 Q.24 Form the cumulative frequency table of less than series from following data : C.I. Frequency 0-10 3 10-20 12 20-30 36 30-40 76 40-50 97 50-60 85 60-70 39 70-80 12 80-90 12 90-100 6
Q.25 Construct a c.f. table for the following data : C.I. Frequency 4-7 3 8-11 10 12-15 12 16-19 8 20-23 5 24-27 9 Q.26 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 Q.27 The water bills (in ruppees) of 32 houses in a certain street for the period 1.1.98 to 31.3.98 are given below : 56, 43, 32, 38, 56, 24, 68, 85, 52, 47, 35, 58, 63, 74, 27, 84, 69, 35, 44, 75, 55, 30, 54, 65, 45, 67, 95, 72, 43, 65, 35, 59. Tabulate the data and present the data as cumulative frequency table using 70-79 as one of the clas intervals. Q.28 The mean weight per student in a group of 7 students is 55 kg. The individual weights of 6 of them (in kg) are 52, 54, 55, 53, 56 and 54. Find the weight of the seventh student. Q.29 The weights (in kg) of 15 students are : 31, 35, 27, 29, 32, 43, 37, 41, 34, 28, 36, 44, 45, 42, 30. Find the median. If the weight 44 kg is replaced by 46 kg and 27 kg by 25 kg, find the new median. Q.30 Find the mode of the following data in each case: (i) 14, 25, 14, 28, 18, 17, 18, 14, 23, 22, 14, 18 (ii) 7, 9, 12, 7, 12, 13, 15, 7, 12, 7, 25, 18, 7 Apply Deviation method to find arithmetic mean in each of the following: Q.31 Class- interval 0–10 10–20 20–30 30–40 40–50 Frequency 9 12 15 10 14 Q.32 Class- interval 0–10 10–20 20–30 30–40 40–50 Frequency 12 11 8 10 9 Q.33 Class- interval 0–10 10–20 20–30 30–40 40–50 Frequency 7 8 12 13 10 Q.34 Class- interval 50–60 60–70 70–80 80–90 90–100 Frequency 9 12 14 15 10 Q.35 Class- interval 20–30 30–40 40–50 50–60 60–70 70–80 Frequency 13 18 20 27 12 10 Q.36 Class- interval 25–35 35–45 45–55 55–65 65–75 Frequency 6 10 8 12 4 Q.37 Class-interval Frequency 0–50 4 50–100 10 100–150 12 150–200 10 200–250 8 250–300 6 Q.38 Class-interval Frequency 0–20 8 20–40 10 40–60 15 60–80 10 80–100 7