This question is Incomplete
Complete Question
What sample size is needed to give a margin of error within ± 13 in estimating a population mean with 99% confidence, assuming a previous sample had s=116
Answer:
The sample size n = 530 samples
Explanation:
Margin of Error formula = z × standard deviation/√n
Margin of Error = ± 13
Standard deviation = 116
z = z score of 99% = 2.58
±13 = 2.58 × 116/√n
Cross Multiply
±13 × √n = 2.58× 116
±13 × √n = 299.28
√n = 299.28/±13
√n = ± 23.0215384615
Square both sides
(√n)² = (±23.0215384615)²
n = 529.991233134
Approximately , n = 530 samples