First, arrange the numbers: 10, 11, 12, 13, 14, 15. The median is the average of the 3rd and 4th numbers: (12 + 13) / 2 = 12.5.

The mode is 10, as it appears most frequently (three times) in the data set.

The mode is 15, which appears 3 times in the data set.

The mode is 4, as it appears four times, which is more than any other number.

Mean = (1 + 2 + 3 + 4 + 5) / 5 = 3. Variance = [(1-3)² + (2-3)² + (3-3)² + (4-3)² + (5-3)²] / 5 = 2.

All values are the same, so variance = 0.

Arranging the numbers: 5, 8, 12, 15, 20. The median is the middle number, which is 12.

The mode is 9, as it appears most frequently (three times) in the data set.

Total sum = Average * Number of items = 12 * 6 = 72.

The mode is 10, as it appears most frequently (three times) in the data set.

All values are the same, so variance = 0.

The numbers are already in order. The median is the average of the 5th and 6th numbers: (5 + 6) / 2 = 5.5.

Standard deviation is the square root of variance. Therefore, SD = √25 = 5.

Total sum = Mean * Number of elements = 50 * 10 = 500.

Total sum = Mean * Number of items = 12 * 6 = 72.

Total sum = Mean * Number of elements = 30 * 6 = 180.

Mean = Sum / 5. Therefore, Sum = Mean * 5 = 6 * 5 = 30.

Mean = n(n + 1) / (2n) = 10.\n\n(n + 1) / 2 = 10\n\n(n + 1) = 20\n\nn = 19.

Mean = (15 + 18 + 22 + x + 25) / 5 = 20. Solving gives x = 24.

Arranging the data: 3, 5, 7, 9, 11. Median = 7.

For the median to be 9, x must be 9. The ordered set is 3, 7, 9, 9, 15.

Removing 5, which is the mode, leaves 3 as the new mode since it appears twice.

The original mode is 4. Increasing it by 1 gives a new mode of 5.

Arranging the numbers: 3, 5, 7, 8, 12. The median is the middle number, which is 7.

Probability of not A = 1 - P(A) = 1 - 0.4 = 0.6.

Probability of not occurring = 1 - P(event) = 1 - 0.3 = 0.7.

Range = Maximum - Minimum. Therefore, Maximum = Range + Minimum = 20 + 10 = 30.

Standard deviation = √16 = 4. If the minimum is 0, the maximum can be 4, thus range = 4 - 0 = 4.

Standard deviation is the square root of variance. Therefore, SD = √16 = 4.

Standard deviation = √25 = 5.