1 is the estimate of the conditional probability that a chip will melt between the 25th second...

Question:

ρ̂ 1 is the estimate of the conditional probability that a chip will melt between the 25th second and the 30th second, given that it has remained unmelted through the 25th second. Show that about 14% of the chips that have not melted just prior to the 25th second will melt between the 25th and the 30th second.