Answer:
a) The estimated standard deviation of the sampling distribution of the proportion is 0.023
b) the estimated standard deviation have been if he had surveyed only 100 customers is 0.046
Step-by-step explanation:
given information:
the number of sample, n = 400
sample proportion, p = 70% = 0.7
a) standard deviation of a sample proportion is
σ = 
= 
= 0.023
b) if n = 100, so
σ = 
= 
= 0.046
Answer: c
Step-by-step explanation:
105 x 4 = 420
63 x 7 = 441
420 + 441 = 861
(1.9 x 10^5)^3 = 1.9^3 x 10^15 = 6.859 x 10^15
Answer: 4
Explanation:
2^2=2*2=4