- An activity has four elements. The activity is work-measured and the time ® are recorded on continuous basis over five cycles. The observations are given in table:
|
Work Element
|
Observations
|
Rating Factor
|
|
Cycle ® 1
|
2
|
3
|
4
|
5
|
|
1
2
3
4
|
0.50
0.70
1.45
2.75
|
3.30
3.45
4.05
5.25
|
5.70
5.95
6.50
7.60
|
8.20
8.55
9.25
10.35
|
10.85
11.10
11.75
13.05
|
1.1
1.2
1.2
0.8
|
The time r is recorded at the end of work-element
(i) Calculate:
- Normal time of the activity
- Standard time for the activity, if the allowance is 20%
(ii) What is the appropriate sample size for estimating the time for element 2 within ±10% of the true mean with 95% confidence; the standard deviation for the time for element 2 is 0.0742.