Question: Samples of both surface soil and subsoil
Samples of both surface soil and subsoil were taken from eight randomly selected agricultural locations in a particular county. The soil samples were analyzed to determine surface pH and subsoil pH, with the results shown in the accompanying table.
a. Calculate a 90% confidence interval for the mean difference between surface and subsoil pH for agricultural land in this county.
b. What conditions must be met for the interval in Part (a) to be valid?
Transcribed Image Text:
Location 2 3 4 5 6 7 8 Surface pH 6.55 5.98 5.59 6.17 5.92 6.18 6.43 5.68 Subsoil pH 6.78 6.14 5.80 5.91 6.10 6.01 6.18 5.88
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