## Friday, April 15, 2011

### Data Handling (Mean from Frequency Table)

How to calculate Mean from Frequency Table

A. The process
Refer to the following link for information on the process.

B. Notation

B. Question:

source: http://www.mathsisfun.com

1. Take parking spaces as x
Take sigma as E
Take frequency as f

Efx/Ef=(15x1+27x2+8x3+5x4)/(15+27+8+5)
=113/55
=2.05454545454545....

Rounded off=2.05

Ans:2.05

2. 1(15) + 2(27) + 3(8) + 4(5) = 113
15+27+8+5 = 55
113÷55= 2.054545454545........

We round off the answer to 3 sig fig which will give us 2.05

Ans: 2.05

3. 1(15) + 2(27) + 3(8) + 4(5) = 113
113÷the frequency=113÷(15+27+8+5)=113÷2.0545454 and so on with the 5s and 4s. :)
We will round off the number to 3 significant figures, so the answer is 2.05.

4. This comment has been removed by the author.

5. 1(15) + 2(27) + 3(8) + 4(5) / 15+27+8+5
= 113/55
=2.0545454545454545454545454545454545454545454545454545454545454545454545454545454545454545........( Maximum Limit Of Intel Core 2 Duo Chips Reached )( P.S. Number is indefinite )

≈2.05

6. (1x15)+(2x27)+(3x8)+(4x5)=113
15+27+8+5=55

113/55~~2.05

7. ∑ƒx 1(15) + 2(27) + 3(8) + 4(5)
mean = ---- = mean = ---------------------------
∑ƒ 15 + 27 + 8 + 5

≈2.05

8. Let the: 1) Number of Parking Spaces be x
2) Number of frequency be f

∑fx: 1(15)+2(27)+3(8)+4(5)=113
∑f: 15+27+8+5=55

Mean number: 113÷55≈2.054 ( 4 Significant Figures )
≈2.05 ( 3 Significant Figures )

9. 1st: Find the sum of the parking spaces multiplied by the frequency

(1 x 15) + (2 x 27) + (3 x 8) + (4 x 5) = 113

2nd: Find the sum of the frequency-

15 + 27 + 8 + 5=55

3rd: Find the mean by dividing the sum of the parking spaces multiplied by the frequency and the frequency itself.

113 / 55 = 2.05 (3 SigFig)

Ans = 2.05

10. (1x15=15)+(2x27=54)+(3x8=24)=(4x5=20)=113
15+27+8+5 = 55
113÷55= 2.054545454545.....≈2.05

11. (1x15)+(2x27)+(8x3)+(4x5)=113
15+27+8+5=55
113÷55=2.054(4SF)2.05(3SF)

12. 1(15) + 2(27) + 3(8) + 4(5) = 113
15+27+8+5 = 55
113÷55= 2.054545454545........

Round off to 3 sig. fig. = 2.05

13. 1(15)+2(27)+3(8)+4(5)=113
15+27+8+5=55

113/55=2.05454.............

So you round it if 3 significant figure which is=2.05

14. ∑ƒx/∑ƒ
15(1)+27(2)+8(3)+5(4)/15+27+8+5
=113/55≈2.05

15. ∑ƒx/∑ƒ = 15(1)+27(2)+8(3)+5(4)/15+27+8+5 = 2.054545454.....≈2.05 (rounded to 3 sig. figures)

Mean number of parking spaces: 2.05

16. 1x15+2x27+3x8+5x4=15+27+8+5=2.0545454545......=2.05

17. 1(15) + 2(27) + 3(8) + 4(5)=113
113/15+27+8+5≈2.05

18. 15x1+27x2+8x3+5x4=113(frequency times score)
15+27+8+5=55(total frequency)
113/55 (round of to 3 sig. fig.) is 2.05

19. @Ragul:
You dun need to continue putting those numbers in, just round it off.

20. 1(15)+2(27)+3(8)+4(5)=113
15+27+8+5=55
113÷55≈2.05
Ans:2.05

21. (1x15) + (2x27) + (3x8) + (4x5) = 113
15 + 27 + 8 + 5 = 55
113 divided by55≈2.05 (When rounded of to 3 significant figures)

22. 1(15) + 2(27) + 3(8) + 4(5) = 113
15 + 27 + 8 + 5 = 55
113/55 = 2.05 (rounded off to 3 sig. figures)

The mean number of parking spaces is 2.05.