Coded data · Short practice

Check a final answer, then explain the reasoning on paper. Guest progress stays in this browser; an account saves future checks without overwriting your first result.

Recall

Coding and combined data — objective 1

Maths4U Original · Short practice

The n=15 observations X have mean 12 and population variance 13. Define \(Y=3X+17\). A second disjoint group has 17 Y-values with mean 57.

Find the mean of Y.

Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.

Fresh review variant

Coding and combined data — objective 1

Maths4U Original · Short practice

The n=16 observations X have mean 13 and population variance 14. Define \(Y=4X+18\). A second disjoint group has 18 Y-values with mean 74.

Find the mean of Y.

Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.

Method

Coding and combined data — objective 2

Maths4U Original · Short practice

The n=16 observations X have mean 13 and population variance 14. Define \(Y=4X+18\). A second disjoint group has 18 Y-values with mean 74.

Find the variance of Y.

Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.

Fresh review variant

Coding and combined data — objective 2

Maths4U Original · Short practice

The n=17 observations X have mean 14 and population variance 15. Define \(Y=2X+19\). A second disjoint group has 19 Y-values with mean 51.

Find the variance of Y.

Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.

Apply

Coding and combined data — objective 3

Maths4U Original · Short practice

The n=17 observations X have mean 14 and population variance 15. Define \(Y=2X+19\). A second disjoint group has 19 Y-values with mean 51.

Find the sum of Y in the first group.

Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.

Fresh review variant

Coding and combined data — objective 3

Maths4U Original · Short practice

The n=18 observations X have mean 15 and population variance 16. Define \(Y=3X+20\). A second disjoint group has 20 Y-values with mean 69.

Find the sum of Y in the first group.

Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.

Check understanding

Coding and combined data — objective 4

Maths4U Original · Short practice

The n=18 observations X have mean 15 and population variance 16. Define \(Y=3X+20\). A second disjoint group has 20 Y-values with mean 69.

Find the mean of all Y-values in both groups.

Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.

Fresh review variant

Coding and combined data — objective 4

Maths4U Original · Short practice

The n=19 observations X have mean 16 and population variance 17. Define \(Y=4X+21\). A second disjoint group has 21 Y-values with mean 89.

Find the mean of all Y-values in both groups.

Enter one number or fraction. Use at least six decimal places when needed; a distribution calculator may be used for probabilities.

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