The life of a certain type of battery, BBB hours, is normally distributed with a mean of 120 hours and a standard deviation of 16 hours.
Find P(B>144)P(B > 144)P(B>144).
Find the value of kkk such that P(B<k)=0.15P(B < k) = 0.15P(B<k)=0.15.
Ben is preparing for a 12-hour recording session. Given that the battery has already been in use for 144 hours,
find the probability that the battery will not run out before the session is completed.
616 exam-style questions on Edexcel A Level Maths The Normal Distribution, covering 3.1 The Normal Distribution, 3.2 Finding Probabilities for Normal Distributions, 3.3 The Inverse Normal Distribution Function, 3.4 The Standard Normal Distribution, 3.5 Finding the mean and standard deviation, 3.6 Approximating a Binomial Distribution, and 3.7 Hypothesis Testing with the Normal Distribution. Each one has a worked solution and a mark scheme showing where the marks go.