A researcher wants a 95% z-interval with margin of error at most 2 units. From a pilot study, sigma = 8.
What is the minimum sample size needed?
- A
16
- Bcheck_circle
62
- C
8
- D
32
Explanation
n >= (z* sigma/ME)^2 = (1.96 * 8/2)^2 = (7.84)^2 = 61.5. Round up to 62.