In a genetics experiment, investigators looked at 300 chromosomes of a particular type a...

In a genetics experiment, investigators looked at 300 chromosomes of a particular type and counted the number of sister-chromatid exchanges on each (“On the Nature of Sister-Chromatid Exchanges in 5-Bromodeoxyuridine- Substituted Chromosomes,” Genetics, 1979: 1251–1264). A Poisson model was hypothesized for the distribution of the number of exchanges. Test the fit of a Poisson distribution to the data by first estimating μ and then combining the counts for x = 8 and x = 9 into one cell.