Edexcel S3 2014 June — Question 5

Exam BoardEdexcel
ModuleS3 (Statistics 3)
Year2014
SessionJune
TopicChi-squared distribution

5. A research station is doing some work on the germination of a new variety of genetically modified wheat. They planted 120 rows containing 7 seeds in each row.
The number of seeds germinating in each row was recorded. The results are as follows
Number of seeds germinating in each row01234567
Observed number of rows2611192532169
  1. Write down two reasons why a binomial distribution may be a suitable model.
  2. Show that the probability of a randomly selected seed from this sample germinating is 0.6 The research station used a binomial distribution with probability 0.6 of a seed germinating. The expected frequencies were calculated to 2 decimal places. The results are as follows
    Number of seeds germinating in each row01234567
    Expected number of rows0.202.06\(s\)23.22\(t\)31.3515.683.36
  3. Find the value of \(s\) and the value of \(t\).
  4. Stating your hypotheses clearly, test, at the \(1 \%\) level of significance, whether or not the data can be modelled by a binomial distribution.