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The means of two samples of sizes 500 an...

The means of two samples of sizes 500 and 600 were respectively 186 and 175. The corresponding standard deviations were respectively 9 and 10. The variable studied was height in centimetres. Obtain the mean and variance of the combined sample.

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The correct Answer is:
Therefore, the required variance of the combined sample is `121.36cm^(2)`.
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