Question

How do I make this bell curve

Answer 1

The mean you found is correct, but the standard deviation is not. Recall that the standard deviation $\sigma_s$ ($s$ for sample) of $n$ points is given by

$\sigma_s=\sqrt{\dfrac1{n-1}\displaystyle\sum_{1\le i\le n}(x_i-\bar x)^2}$

where $n=10$ is the sample size, $\bar x=3740$ is the sample mean, and $x_i$ are the prices listed in the circled column. So

$\sigma_s=\sqrt{\dfrac{(3640-3740)^2+(7595-3740)^2+\cdots+(3390-3740)^2}{10-1}}$

$\implies\sigma_s\approx1443.98\approx1444$

I can't tell if you need to provide any more info beyond this, but given there's a plot of a generalized bell curve, I think you're also supposed to label the plot.

At the center of the bell-shaped/normal distribution is the mean. Notice there are three tick marks to either side of the mean - these are probably supposed to represent prices that fall exactly 1, 2, and 3 standard deviations from the mean. These are, from left to right,

$\bar x-3\sigma_s\approx3740-3(1444)=-592$

$\bar x-2\sigma_s\approx3740-2(1444)=852$

$\bar x-\sigma_s\approx2296$

$\bar x+\sigma_s\approx5184$

$\bar x+2\sigma_s\approx6628$

$\bar x+3\sigma_s\approx8072$