Question:-
The management is interested to know the percentage of idle time of equipment. The trial study showed that percentage of idle time would be 20%. The number of random observations necessary for 95% level of confidence and ± 5% accuracy Is
Option (A)
6400
Option (B)
1600
Option(C)
640
Option(D)
160
Correct Option:
(A)
Question Solution:
P.S. = K. sp Hence it is given P = 0.20
S = 0.05
K = 2(95%)
Þ
Þ
Þ n = 6400
Where P is fraction occurrence of events
n = number of observations
s = Precision factor
k = Confidence factor
(k/s) = Confidence precision factor
question-answer-faq-8760