Question

Listed below are measured amounts of lead​ (in micrograms per cubic​ meter, or μg/m3​)in the air. The EPA has established an air quality standard for lead of 1.5 μg/m3.he measurements shown below were recorded at a building on different days. Use the given values to construct a 95​% confidence interval estimate of the mean amount of lead in the air. Is there anything about this data set suggesting that the confidence interval might not be very​ good?

5.40, 1.10, 0.39, 0.77, 0.72, 0.90

Answer 1

For the given sample

Create the following table.

data	data-mean	(data - mean)2
5.40	3.8533	14.84792089
1.10	-0.4467	0.19954089
0.39	-1.1567	1.33795489
0.77	-0.7767	0.60326289
0.72	-0.8267	0.68343289
0.90	-0.6467	0.41822089

Now t table value for 5 df is 2.570

So Margin of Error is

Hence CI is

We see that width is too high, hence confidence interval might not be very​ good