NCERT 2022 | रेशो से वस्त्र तक - L9| From fiber to fabric | CLASS7 विज्ञान | 8PM Class by Amba Ma'am

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?

A company manufactures car batteries of a particular type. The lives (in years) of 40 such batteries were recorded as follows: 2.6 3.0 3.7 3.2 2.2 4.1 3.5 4.5 3.5 2.3 3.2 3.4 3.8 3.2 4.6 3.7 2.5 4.4 3.4 3.3 2.9 3.0 4.3 2.8 3.5 3.2 3.9 3.2 3.2 3.1 3.7 3.4 4.6 3.8 3.2 2.6 3.5 4.2 2.9 3.6 Construct a grouped frequency distribution table for this data, using class intervals of size 0.5 starting from the interval 2 - 2.5.

Satish is 9 ranks ahead of Ajay in the class of 39 students. If Ajay’s rank is 15th from the last, then what is Satish’s rank from the start? सतीश 39 छात्रों की कक्षा में अजय से 9 रैंक आगे है। अगर अजय की रैंक आखरी से 15वीं है, तो सतीश की रैंक शुरू से क्या है?

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 .

Find the mean deviation from the mean for the following data: Classes 0-100 100-200 200-300 300-400 400-500 500-600 600-700 700-800 Frequencies 4 8 9 10 7 5 4 3