In a manufacturing process for specialized solar cells, the probability that a cell is classified as 'High Efficiency' grade is 0.35.
Find the probability that
in a random sample of 8 cells, exactly 2 are classified as High Efficiency.
in a random sample of 20 cells, the number of High Efficiency cells is more than 10.
A quality control manager inspects a large delivery of 400 cells.
Using a suitable approximation, determine the probability that the delivery contains fewer than 130 High Efficiency cells.
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.