NCERT 2022 | दहन और ज्वाला - L9 | Combustion and Flame | CLASS 8 विज्ञान | 7 PM Class by Amba Mam

Ratio of the fares of First ,Second and Third class catogory of a train , between two stations is 10:7:2 and the ratio of passenger travelling in these category is 4:9:17 respectively .If the fare is increased by 1/4 in First class , 1/8 in second class and decreased by 10% i Third Class and the ratio of number of passenger in the category remains same .If the total amount received of Rs. 60590 , then find the total amount received from thrid class category .

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).

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.

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?

Consider the marks, out of 100, obtained by 51 students of a class in a test, given in Table 14.9. M a r k s"N u m b e r o f S t u d e n t s"0-10 5 10-20 10 20-30 4 30-40 6 40-50 7 50-60 3 60-70 2 70-80 2 80-90 3 90-100 9Tot a l 51 Draw a freque

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 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 cliess being 15-20 (where 20 is not included)