A logistics company finds that 35% of their long-distance delivery drones require a battery recalibration after each flight.
State a distribution that is suitable to model the number of drones requiring recalibration in a random selection of 20 drones.
State two conditions for the distribution in part (a) to be a valid model.
Find the probability that: exactly 8 drones in a selection of 20 require recalibration,
Find the probability that: fewer than 12 drones in a selection of 40 require recalibration.
A maintenance supervisor notes that the technical team will be overwhelmed if more than 100 drones in a daily batch of 250 require recalibration.
Using a suitable approximation, find the probability that the technical team will be overwhelmed in a particular batch of 250 drones.
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.