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A traffic engineer plans to estimate the average number of cars that pass through an intersection each day. Based on previous studies the standard deviation is believed to be 52 cars. She wants to estimate the mean to within ± 10 cars with 90 percent confidence. The needed sample size for n is:

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    eric's note book has 30 pages.he wants to write a number on each page. how many digits will he wite in his note book

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    n=8

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