Question

The mean percent of childhood asthma prevalence in 43 cities is 2.18​%. A random sample of 33 of these cities is selected. What is the probability that the mean childhood asthma prevalence for the sample is greater than 2.6​%? Interpret this probability. Assume that sigma equals 1.35​%.

Answer 1

Solution :

Given that ,

= 2.18%

= / n = 1.35% / 33 = 0.235%

P( > 2.6%) = 1 - P( < 2.6% )

= 1 - P[( - ) / < (2.6% - 2.18%) / 0.235%]

= 1 - P(z < 1.79)   

= 1 - 0.9633

= 0.0367

The probability that a randomly selected 33 childhood asthma prevalence for the sample is greater than 2.6% is 0.0367