CAIE FP2 2009 June — Question 9

Exam BoardCAIE
ModuleFP2 (Further Pure Mathematics 2)
Year2009
SessionJune
TopicChi-squared distribution

9 The proportions of blood types \(\mathrm { A } , \mathrm { B } , \mathrm { AB }\) and O in the Australian population are \(38 \% , 10 \% , 3 \%\) and \(49 \%\) respectively. In order to test whether the population in Sydney conforms to these figures, a random sample of 200 residents is selected. The table shows the observed frequencies of these types in the sample.
Blood TypeABABO
Frequency57249110
Carry out a suitable test at the 5\% significance level. Find the smallest sample size that could be used for the test.