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2.4.4 Mean and variance of the binomial (A-level only)

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Question 14

In a manufacturing facility for precision sensors, the probability of a sensor having a calibration error is p=0.12p = 0.12p=0.12. Errors occur independently in each sensor.

a.

Find the probability that in a random sample of 25 sensors, there will be

(i) exactly 4 sensors with a calibration error,

(ii) at least 6 sensors with a calibration error.

[4]
b.

In a large batch of 600 sensors, use a suitable approximation to find the probability that the number of sensors with calibration errors is more than 80.

[5]

2.4.4 Mean and variance of the binomial (A-level only) Questions

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  3. /2.4.4 Mean and variance of the binomial (A-level only)