Answer: 24.60 minutes (2dp)
Step-by-step explanation:
The question is essentially asking that we find the Standard Time it takes to serve a customer.
To do this we would have to calculate the averages of the different elements and then use this to find the normal time which we can then use to find the Standard Time.
Element 1
= (3 + 4 + 4 + 3 + 3)/5
= 3.4
Element 2
= ( 9 + 8 + 10 + 11 + 10)/5
= 9.6
Element 3
= ( 7 + 8 + 6 + 7 + 8)/5
= 7.2
We then calculate the normal times by multiplying each of the individual means with their performance ratings.
That would be,
Element A
= 3.4 * 70%
= 2.38
Element B
= 9.6 * 110%
= 10.56
Element C
= 7.2 * 120%
= 8.64
We then add up the normal times to get the total normal time
= 2.38 + 10.56 + 8.64
= 21.58 minutes
Now we can solve for the standard time using this formula,
Standard time = Normal time (1+Allowance factor)
= 21.58 ( 1 + 0.14)
= 24.6012 minutes
= 24.60 minutes (2dp)
The time per unit customer served is 24.60 minutes.
If you need any clarification please do comment. Cheers.