A manufacturer produces high-precision capacitors. The capacitance, CCC millifarads (mF), follows a normal distribution with a mean of 220 mF and a standard deviation of 12 mF.
Determine the probability that a randomly chosen capacitor has a capacitance greater than 241 mF.
Given that P(c<C<220)=0.42P(c < C < 220) = 0.42P(c<C<220)=0.42, calculate the value of ccc.
Two capacitors are selected at random. Calculate the probability that exactly one of them has a capacitance between ccc mF and 220 mF.
390 exam-style questions on OCR A Level Maths 2.4 Statistical Distributions, covering 2.4.1 Discrete probability distributions, 2.4.2 Binomial distribution as a model, 2.4.3 Calculating binomial probabilities, 2.4.4 Mean and variance of the binomial (A-level only), 2.4.5 Normal distribution as a model (A-level only), 2.4.6 Probabilities using the normal distribution (A-level only), 2.4.7 Links to histograms, mean and standard deviation (A-level only), and 2.4.8 Selecting an appropriate distribution (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.