4.5 Statistical distributions (A-level only)

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Question 4

48%

A machine produces metal rods whose lengths, $L$ , follow a normal distribution. It is found that 15% of the rods have a length less than 15.2 cm and 10% of the rods have a length greater than 16.5 cm.

Find the mean and standard deviation of the rod lengths.

[6]

4.5 Statistical distributions (A-level only)

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Question 4

48%

A machine produces metal rods whose lengths, $L$ , follow a normal distribution. It is found that 15% of the rods have a length less than 15.2 cm and 10% of the rods have a length greater than 16.5 cm.

Find the mean and standard deviation of the rod lengths.

[6]

4.5 Statistical distributions (A-level only)

Question 4

4.5 Statistical distributions (A-level only) Questions

4.5 Statistical distributions (A-level only)

Question 4

4.5 Statistical distributions (A-level only) Questions