In 2008 the Better Business Bureau settled 75% of complaints they received (USA Today, March 2, 2009). Suppose you have

[answerhappygod]

In 2008 the Better Business Bureau settled 75% of complaints
they received (USA Today, March 2, 2009). Suppose you have been
hired by the Better Business Bureau to investigate the complaints
they received this year involving new car dealers. You plan to
select a sample of new car dealer complaints to estimate the
proportion of complaints the Better Business Bureau is able to
settle. Assume the population proportion of complaints settled for
new car dealers is .75, the same as the overall proportion of
complaints settled in 2008. Use z-table.
p = (to 2 decimals)
standard error of the proportion σ( p
) = (to 4 decimals)
p = (to 2 decimals)
standard error of the proportion σ( p ) = (to 4
decimals)
The probability of the sample
proportion being within .04 of the population mean was
[Increased/Redued] with the smaller sample. So
there is a [Gain/Loss] in precision by
[Increasing/Decreasing] the sample size from 200
to 450. It is always convenient using a larger sample, so long as
the extra cost of using the larger sample size [is too
great/is not too great].