OCR S1 Specimen — Question 1

Exam BoardOCR
ModuleS1 (Statistics 1)
SessionSpecimen
TopicMeasures of Location and Spread
TypeCalculate variance from summary statistics

1 Janet and John wanted to compare their daily journey times to work, so they each kept a record of their journey times for a few weeks.
  1. Janet's daily journey times, \(x\) minutes, for a period of 25 days, were summarised by \(\Sigma x = 2120\) and \(\Sigma x ^ { 2 } = 180044\). Calculate the mean and standard deviation of Janet's journey times.
  2. John's journey times had a mean of 79.7 minutes and a standard deviation of 6.22 minutes. Describe briefly, in everyday terms, how Janet and John's journey times compare.