CAIE S1 2020 Specimen — Question 3

Exam BoardCAIE
ModuleS1 (Statistics 1)
Year2020
SessionSpecimen
TopicDiscrete Probability Distributions
TypeCalculate Var(X) from table

3 A b clb sed 6 p p rb ck ad 2 h r ck b to Mrs Ho . Sb cb es 4 6 tb se b at rach to take with b r o b id y. Th rach \& riable \(X\) rep esen s tb m br \(\mathbf { b }\) p \(\mathbf { p }\) rb ck b sh cb es.
  1. Sth that th p b b lityt \(\mathbf { h }\) tsb cb es extlye perb clb is \(\frac { 3 } { 14 }\). [R
  2. Draw up b pb b lityd strib in tab e fo \(X\).
  3. Yu reg it h t \(\mathrm { E } ( X ) = 3\) Fid \(\operatorname { Var } ( X )\).