Edexcel S1 2016 October — Question 5

Exam BoardEdexcel
ModuleS1 (Statistics 1)
Year2016
SessionOctober
TopicNormal Distribution
TypeQuadratic relationship μ = kσ²

  1. The label on a jar of Amy’s jam states that the jar contains about 400 grams of jam. For each jar that contains less than 388 grams of jam, Amy will be fined \(\pounds 100\). If a jar contains more than 410 grams of jam then Amy makes a loss of \(\pounds 0.30\) on that jar.
The weight of jam, \(A\) grams, in a jar of Amy's jam has a normal distribution with mean \(\mu\) grams and standard deviation \(\sigma\) grams. Amy chooses \(\mu\) and \(\sigma\) so that \(\mathrm { P } ( A < 388 ) = 0.001\) and \(\mathrm { P } ( A > 410 ) = 0.0197\)
  1. Find the value of \(\mu\) and the value of \(\sigma\). Amy can sell jars of jam containing between 388 grams and 410 grams for a profit of \(\pounds 0.25\)
  2. Calculate the expected amount, in £s, that Amy receives for each jar of jam.