document.write( "Question 367001: 1. A 99% confidence interval estimate for a population mean was computed to be (29.2, 46.6). Determine the mean of the sample, which was used to determine the interval estimate (show all work).\r
\n" ); document.write( "\n" ); document.write( "2. A study was conducted to estimate the mean amount spent on birthday gifts for a typical family having two children. A sample of 170 was taken, and the mean amount spent was $248.72. Assuming a standard deviation equal to $48.31, find the 90% confidence interval for m, the mean for all such families (show all work).
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Algebra.Com's Answer #261637 by robertb(5830)\"\" \"About 
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1. (29.2 + 46.6)/2 = 37.9, the sample mean.
\n" ); document.write( "2. 248.72 +-(1.645)*(48.31)/\"sqrt%28170%29\"= 248.72+-6.095, so the 90% C.I. is
\n" ); document.write( "(242.625, 254.815).
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