Past exam of the mathematical and Computational Biology course of the University of Cambridge / 2025 / Paper 2 / 5 / b / Solution

For an exponential distribution, the survival function at the median equals one half. Thus $e^{-10\delta }=1/2$, andThe corresponding mean care time is $1/\delta =10/\ln 2\approx 14.43$ days; a ten-day median should not be substituted as the mean.