संश्लेषित रेशे एवं प्लास्टिक - L9 | NCERT प्रश्न अभ्यास |Class 8 विज्ञान | 7 PM Class by Amba Mam

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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 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 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 distance (in km) of 40 engineers from their residence to their place of work were found as follows: 5 3 10 20 25 11 13 7 12 31 19 10 12 17 18 11 32 17 16 2 7 9 7 8 3 5 12 15 18 3 12 14 2 9 6 15 15 7 6 12 Construct a grouped frequency distribution table with class size 5 for the data given above taking the first interval as 0-5 (5 not included). What main features do you observe from this tabular representation?

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

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?

Following are the marks obtained by a batch of 10 students in a certain class test in Statistics (X) and Accountancy (Y) : {:("Roll Number",1,2,3,4,5,6,7,8,9,10),("Statistics (X)",63,64,62,32,30,60,47,46,35,28),("Accountancy(Y)",68,66,35,42,26,85,44,80,33,72):} In which subject is level of Knowledge of students higher ?

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