The discharge duration, D D\,D minutes, of a specialized drone battery is modeled by a normal distribution with a mean of 122.5 minutes and a standard deviation of 3.2 minutes.
Find the probability that a randomly selected battery has a discharge duration exceeding 128 minutes.
Determine the value of d d\,d such that P(122.5<D<d)=0.38P(122.5 < D < d) = 0.38P(122.5<D<d)=0.38.
Two batteries are selected at random from the production line.
Calculate the probability that exactly one of these batteries has a discharge duration between 122.5 minutes and d d\,d minutes.
147 exam-style questions on OCR A Level Maths 2.4.6 Probabilities using the normal distribution (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.