Question

**Pollution and altitude:** In a random sample of
320 cars driven at low altitudes, 50 of them exceeded a standard of
10 grams of particulate pollution per gallon of fuel consumed. In
an independent random sample of 135 cars driven at high altitudes,
17 of them exceeded the standard. Can you conclude that the
proportion of high-altitude vehicles exceeding the standard is less
than the proportion of low-altitude vehicles exceeding the
standard? Let p1 denote the proportion of low-altitude vehicles
exceeding the standard and p2 denote the proportion of
high-altitude vehicles exceeding the standard. Use the =α0.1 level
of significance and the P-value method. Round intermediate steps to
six decimal places, if necessary.

a.) State the null and alternate hypotheses.

b.) Compute the test statistic.

c.)Compute the P-value.

d.) Interpret the

e.) P-value.

Answer #1

In a random sample of 340 cars driven at low altitudes, 46 of
them exceeded a standard of 10 grams of particulate pollution per
gallon of fuel consumed. In an independent random sample of 85 cars
driven at high altitudes, 21 of them exceeded the standard. Can you
conclude that the proportion of high altitude vehicles exceeding
the standard is greater than the proportion of low altitude
vehicles exceeding the standard?

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