CAIE S2 2004 June — Question 4

Exam BoardCAIE
ModuleS2 (Statistics 2)
Year2004
SessionJune
TopicMeasures of Location and Spread
TypeStandard unbiased estimates calculation

4 Packets of cat food are filled by a machine.
  1. In a random sample of 10 packets, the weights, in grams, of the packets were as follows.
    \(\begin{array} { l l l l l l l l l l } 374.6 & 377.4 & 376.1 & 379.2 & 371.2 & 375.0 & 372.4 & 378.6 & 377.1 & 371.5 \end{array}\)
    Find unbiased estimates of the population mean and variance.
  2. In a random sample of 200 packets, 38 were found to be underweight. Calculate a \(96 \%\) confidence interval for the population proportion of underweight packets.