The marks of 800 candidates in an examination were normally distributed with a mean of 45...

Question

Question

The marks of 800 candidates in an examination were normally distributed with a mean of 45

marks and standard deviation of 20 marks.

If 5% of the candidates obtained a distinction by scoring X marks or more, estimate the value of X ; [4 Marks]
Estimate the interquartile range of the marks. [6 Marks]

Answer 1

Answer #1

Answer 2

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