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The closing prices of two shares X and Y over ten days are: X: 35, 54, 52, 53, 56, 58, 52, 50, 51, 49 Y: 108, 107, 105, 105, 106, 107, 104, 103, 104, 101 Using the coefficient of variation, determine which share's price is more stable.

1. X is more stable
2. Y is more stable
3. Both are equally stable
4. Cannot be determined

Correct answer: Y is more stable

Solution

The coefficient of variation of Y is far smaller than that of X (Y has a high mean near 105 with little spread, while X has an outlier 35 inflating its spread), so share Y is more stable.

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