Circuit board capacitors. Use the data of Table 2.1, but omit the data on board 4.
(a) Calculate the pooled estimate 
of the assumed common value of the binomial proportion.
(b) Calculate two-sided approximate 90% confidence limits for the common proportion.
(c) Calculate the test statistic (2.4). How many degrees of freedom does it have? Look up the 99 and 99.9% points of the corresponding chi-square distribution.
(d) Is the test statistic statistically significant? Which boards contribute significantly to the test statistic?
(e) Is the chi-square approximation adequate? Why? data on board 4.
Table 2.1
