A simple random sample consists of three observations 1, 3, 5. The point estimate of the population standard deviation is : 2.5324.2

The question seems to be asking for the calculation of the standard deviation of a simple random sample. However, the question is not complete. Please provide the complete question for a more accurate response.

Here is a general step-by-step guide on how to calculate the standard deviation:

1. Find the mean (average) of the data set. This is done by adding all the numbers in the data set and then dividing by the number of observations. In this case, the mean would be (1+3+5)/3 = 3.

2. Subtract the mean from each number in the data set and then square the result. This gives you the squared deviations. For this data set, the squared deviations would be (1-3)^2 = 4, (3-3)^2 = 0, and (5-3)^2 = 4.

3. Find the average of these squared deviations. This is done by adding all the squared deviations and then dividing by the number of observations. In this case, the average squared deviation would be (4+0+4)/3 = 2.6667.

4. Take the square root of the average squared deviation. This gives you the standard deviation. In this case, the standard deviation would be √2.6667 = 1.63299.

Please note that the standard deviation calculated here does not match the one provided in the question (2.5324.2), which seems to be a typographical error.