Round your answer to two decimal places Dartmouth Distribut
Round your answer to two decimal places.
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Dartmouth Distribution Warehouse makes deliveries of a large number of products to its customers.
It is known that 84% of all the orders it receives from its customers are delivered on time. Let (p-hat) be
the proportion of orders in a random sample of 100 that are delivered on time. Find the probability that
the value of (p-hat) will be between .81 and .87
Round your answer to four decimal places.
Solution
P(-15000<(xbar-mu)<15000)
= P(-15000/(80000/sqrt(70)) <(xbar-mu)/(s/vn) <15000/(80000/sqrt(70))
=P(-1.57<Z<1.57) = 0.88 (from standard normal table)
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P(0.81<phat<0.87)
= P((0.81-0.84)/sqrt(0.84*(1-0.84)/100) <(phat-p)/sqrt(p*(1-p)/n) <(0.87-0.84)/sqrt(0.84*(1-0.84)/100))
=P(-0.82<Z<0.82)
=0.5878 (from standard normal table)
