9709 · topic questions
Linear combinations of random variables
9 past-paper questions on Linear combinations of random variables
The random variable S is the sum of 100 independent values of W and 200 independent values of X. (ii) Use a suitable…
Practise the full question →Use approximating distributions to find the probability that the total number of lemon sweets in the 10 bags is less than the…
Practise the full question →The random variable X has the distribution N(31.2, 10.4²). Two independent random values of X, denoted by X₁ and X₂, are chosen.…
Practise the full question →The masses, in kilograms, of small and large bags of wheat have the independent distributions N(16.0,0.4) and N(51.0,0.9)…
Practise the full question →Find P(X₁ > 2X₂ −3).
Practise the full question →The times, in minutes, taken by students to complete a test are normally distributed with mean 125 and variance 50. Two students…
Practise the full question →Find the probability that during a randomly chosen 5-minute period the total number of customers arriving at both desks is less…
Practise the full question →At an entertainment centre, the cost for using a particular video game is $0.40 per minute. The number of minutes for which…
Practise the full question →Each day, 35 people independently use the video game. (b) Find the mean and variance of the total amount paid by 35 people.
Practise the full question →
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Linear combinations of random variables (9709) past-paper questions — marked instantly
These are real Cambridge Mathematics past-paper questions on Linear combinations of random variables. Open one, attempt it, then upload your working — MarkScheme grades it against the official 9709 mark scheme so you see exactly where the marks are won and lost on this topic.
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