Q.1 Calculate arithmetic mean of the following data :
profit (in rs) : 0-10 10-2020-30 30-40 40-50 50-60
no of shops : 1218 27 20 17 16
Q.2. A candidate obtains 46% marks in english , 67% in mathematics , 50% in hindi 72% in history and 58% in economics . it is agreed to give triple weight to marks in english and double weight to marks in mathematics as compared to other subjects . calculate weighted mean . Also compare it with simple arithmetic mean .
Q.3. Calculate combined mean :
section mean marks no. of students
A 75 50
B 60 60
C 55 50
Ans. 2) Let the weight of other three subjects (i.e. Hindi, History and Economics) be 10. Therefore, weight for English is 30 (3×10) and weight for Mathematics (2×10).
Subject | Marks (X) | Weight (W) | WX |
English | 46 | 30 | 1380 |
Mathematics | 67 | 20 | 1340 |
Hindi | 50 | 10 | 500 |
History | 72 | 10 | 720 |
Economics | 58 | 10 | 580 |
|
| ΣW = 80 | ΣWX= 4520 |
Thus, the weighted mean of the marks is 56.5
Ans. 3)
Section | Mean Marks
| Number of Students (N) |
A |
|
|
B |
|
|
C |
|
|
Combined Arithmetic Mean
Thus, combined mean marks is 63.2
Due to paucity of time we providing solutions to only two of your question. Try solving the remain question yourself and in case of any difficulty do get back to us.