Figure the mean, median and standard deviation for the number of words learned by seven infants. I beleive the mean is 45.5 and the median is 10.The numbers are 10,12,8,0,3,40,and 18.

How can the mean be much more than any of the numbers?

10 + 12 + 8 + 0 + 3 + 40 + 18 = 91
91/7 = 13

The median is 10.

To find the mean, median, and standard deviation for the number of words learned by seven infants, you can follow these steps:

1. Mean:
To calculate the mean, you need to sum up all the values and divide by the total number of values. In this case, the sum of the numbers is 10 + 12 + 8 + 0 + 3 + 40 + 18 = 91. Divide 91 by the total number of values, which is 7, to find the mean: 91 / 7 = 13.

Therefore, the mean is 13, not 45.5 as you suggested.

2. Median:
To find the median, you need to arrange the numbers in ascending order and find the middle value. In this case, the numbers in ascending order are 0, 3, 8, 10, 12, 18, and 40. Since there are 7 numbers, the middle value is the fourth number, which is 10.

Therefore, the median is 10, not 10 as you suggested.

3. Standard Deviation:
To calculate the standard deviation, you first need to find the deviation of each number from the mean. The deviations are as follows: -3, -1, -5, -13, -10, 27, and 5.

Next, square each deviation (i.e., multiply each deviation by itself): 9, 1, 25, 169, 100, 729, and 25.

Then, calculate the mean of these squared deviations by summing them up and dividing by the total number of values (which is 7): (9 + 1 + 25 + 169 + 100 + 729 + 25) / 7 = 331 / 7 ≈ 47.3.

Finally, take the square root of the mean of the squared deviations to find the standard deviation: √47.3 ≈ 6.88.

Therefore, the standard deviation is approximately 6.88.

In summary, the correct calculations are:
Mean = 13
Median = 10
Standard Deviation ≈ 6.88