CAIE S2 2023 March — Question 1

Exam BoardCAIE
ModuleS2 (Statistics 2)
Year2023
SessionMarch
TopicLinear combinations of normal random variables
TypeConfidence interval for single proportion

1 Anita carried out a survey of 140 randomly selected students at her college. She found that 49 of these students watched a TV programme called Bunch.
  1. Calculate an approximate \(98 \%\) confidence interval for the proportion, \(p\), of students at Anita's college who watch Bunch.
    Carlos says that the confidence interval found in (a) is not useful because it is too wide.
  2. Without calculation, explain briefly how Carlos can use the results of Anita's survey to find a narrower confidence interval for \(p\).