91影视

The frequency distribution of the number of males corresponding to the blood platelet count is tabulated.

Thestandard deviationis a measure of dispersion most commonly used for a set of data. For a frequency distribution, the following formula is used:

$s=\sqrt{\frac{n\left[鈭�\left(f脳x^2\right)\right]-{\left[鈭�\left(f脳x\right)\right]}^2}{n\left(n-1\right)}}$

Here,

• the frequencies are denoted by f;
• the class midpoints are denoted by x;
• the sum of frequencies is denoted by n.

The calculations are tabulated below:

Substituting the above values in the formula:

$$\begin{gathered} s=\sqrt{\frac{n\left[鈭�\left(f脳x^2\right)\right]-{\left[鈭�\left(f脳x\right)\right]}^2}{n\left(n-1\right)}} \\ =\sqrt{\frac{153\left(8388188\right)-{\left(34273.5\right)}^2}{153\left(153-1\right)}} \\ =68.4 \end{gathered}$$

Therefore, the computed value of the standard deviation is68.4.

The actual value of standard deviation is 59.5.

The calculated value of the standard deviation equal to 68.4differs from the value obtained from the original list of observations, which is 59.5.

Thus, the two values cannot be considered equal.