Answer:
a ) n = 1667
b) n= 5192
c) n=1500
Step-by-step explanation:
c= 95%
Expected value = E.v= 300 , 170 , 100
R = 35000-10000=25000
σ = R / 4 = 25000 / 4 = 6250
For sample size
b = ( zα/2 / 2σ / E )^2
where 1-α = 0.95 and
zα/2 = 1.96
then putting values one by one of E we get
E.v = 300
n= 1667
E.v = 170
n=5192
E.v =100
n= 1500
so for
a ) n = 1667
b) n= 5192
c) n=1500