Question

Mobile homes are tightly constructed for energy conservation. This can lead to a buildup of indoor pollutants. The paper "A Survey of Nitrogen Dioxide Levels Inside Mobile Homes" discussed various aspects of NO₂ concentration in these structures.

(a) In one sample of mobile homes in the Los Angeles area, the mean NO₂ concentration in kitchens during the summer was 38.42 ppb, and the standard deviation was 11.28. Making no assumptions about the shape of the NO₂ distribution, what can be said about the percentage of observations between 15.86 and 60.98? (Round the answer to the nearest whole number.)
At least ?%

Answer 1

To determine the percentage of observations between 15.86 and 60.98 in the NO₂ concentration in mobile homes, we can use the empirical rule.

Step-by-step explanation:

The mean NO₂ concentration in kitchens during the summer in a sample of mobile homes in the Los Angeles area was 38.42 ppb with a standard deviation of 11.28. To determine the percentage of observations between 15.86 and 60.98, we can use the empirical rule.

The empirical rule states that for a normal distribution, approximately 68% of the data falls within one standard deviation of the mean, 95% falls within two standard deviations, and 99.7% falls within three standard deviations.

So, in this case, we can say that the percentage of observations between 15.86 and 60.98 is approximately 95%.