An operation that has two tasks was observed during 30 minutes; 20 observations were made and 10 units were produced. The performance ratings for each observation are shown in the table below. Use 2 decimals in all the calculations.

1. What is the average performance rating for each task?)
2. Calculate the observed time per unit for each task (in minutes).
3. Calculate the normal time per unit for each task (in minutes, 2 decimals).
4. Given 12% allowances, calculate the standard time, in minutes, for the whole operation.

Observation #	Speed rating
	Task 1	Task 2	Idle
1	110
2		105
3			X
4	115
5	110
6		95
7	105
8	100
9		95
10	115
11	100
12		85
13		80
14		100
15	100
16	110
17		100
18		95
19	115
20	115