संश्लेषित रेशे एवं प्लास्टिक - L12 | रोचक तथ्य प्लास्टिक | Class 8 विज्ञान | 7 PM Class by Amba Mam

the daily minimum temperatures in degrees 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.

The marks obtained (out of 20) by 30 students of a class in a test are as follows: 14, 16, 15, 11, 15, 14, 13, 16, 8, 10, 7, 11, 18, 15, 14, 19, 20, 7, 10, 13, 12, 14, 15, 13, 16, 17, 14, 11, 10, 20. Prepare a frequency distribution table for the above data using class intervals of equal width in which one class interval is 4-8 (excluding 8 and including 4).

The marks obtained by 40 students of class IX in an examination are given below: 18, 8, 12, 6, 8, 16, 12, 5, 23, 2, 16, 23, 2, 10, 20, 12, 9, 7, 6, 5, 3, 5, 13, 21, 13, 15, 20, 24, 1, 7, 21, 16, 13, 18, 23, 7, 3, 18, 17, 16 Present the data in the form of a frequency distribution using the same class size, one such class being 15-20 (where 20 is not included)

The marks obtained by 40 students of class VIII in an examination are given below: 18,8,12,0,8,16,12,5,23,2,16,23,2,10,20,12,9,7,6,5,3,5, 13,21,13,15,20,24,1,7,21,16,13,18,23,7,3,18,17,16 Present the data in the form of a frequency distribution using the same class size, one such class being 15-20 (where 20 is not included).

Thirty children were asked about the number of hours they watched TV programmes 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 12 (i) Make a grouped 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?

The science lecture theatre of a college is 10 m wide and has a dorr at a cormer. A science techer entres at 12 . 00 noon through the dorr and makes 8 rounds along the 10 m wall back and forth during the period and finaal leaves the class room at 12 . 40 p.m. through the same door. Compute the averae speed and average velocity.

Out of 100 students who appeared for the SSC examination from a school 15 students in English ; 12 students in Mathematics; 8 students in Sience 7 studens in Mathematics and Science; 4 students in English and Science 6 students in English and Mathematics; 4 students in all the three subjects could get First calss marks. How many of them have got First class marks.(ii) only in Science (i) only in Mathmatics

CH. 14 STATISTICS Q1 Class 0-8 8-16 16-24 24-32 32-40 Frequency 10 12 26 9 15 e mean of above data by: () Direct method () Assumed mean method (ii) Step deviati iop metod. Q2 The following distribution shows the daily pocket allowance of children of a locali ty. The mean pocket allowance is Rs 20. Find the missing frequency Daily Pocket 0-20 20-40 40-60 0-80 80-100 No. Of Children 7 10 9 13 Q3. The following table shows age distribution of persons in a particular region. Find the: (0) mean age (i)modal age (ili) median age Age? Below!0 Below20 Below30 Below 40, Below 50 Belo No, persons ? 250 190 100 40 15 4 Arithmetic mean of the following frequency distribution is 50. Find the missing frequencies C.I. ? 0-20 20-40 40-60 60-80 80-100 Tota

The following data : 2, 5, 15, 25, 20, 12, 8, 7, 6, 16, 21,17, 30, 32, 23, 40, 51, 15, 2, 9, 57, 19, 25 is grouped in the classes 0 –5, 5 –10, 10 –15 etc. Find the frequency of the class 20 –25.