Exercise for the reader: find what is wrong with the following paragraphs from an article in the New York Times about the high cost of certain cancer drugs.
In the clinical trial that led to approval of the drug, 27 percent of the 109 patients experienced a reduction in tumor size. The reductions lasted a median of 9.4 months.
But considering all the patients in the trial, only 12 percent had a reduction in tumor size that lasted for more than 14 weeks.
Update: from the press release of the pharmaceutical company:
The results of the trial demonstrated that 29 of 109 evaluable patients, or 27%, responded to FOLOTYN. The median duration of response was 287 days, or 9.4 months (range 1-503 days). Thirteen of 109 evaluable patients had a duration of response ≥ 14 weeks (range 98-503 days).
So the median of 29 numbers is 287, and 16 of those numbers are less than 98.