The survival times of adult mosquitoes exposed to a commonly used synthetic pesticide (Phenothrin) follow a normal distribution, with a standard deviation of 15.18 sec.A random sample of 40 mosquitoes has an average survival time of 47.5 sec.What is a 99% confidence interval for the mean survival time?
A) (41.318, 53.682)
B) (41.916, 53.083)
C) (42.700, 52.300)
D) (8.399, 86.601)

Question

Quizplus · Accepted Answer

To calculate a 99% confidence interval for the mean survival time, we use the formula: mean ± (z * (standard deviation / sqrt(n))), where z is the z-score corresponding to the confidence level (for 99%, z ≈ 2.576), standard deviation is given as 15.18, and n is the sample size (40). Plugging in the values: 47.5 ± (2.576 * (15.18 / sqrt(40))) gives us the interval (41.318, 53.682).

The Survival Times of Adult Mosquitoes Exposed to a Commonly