Comment on Activity 2

Since all the values are equally likely, the probability density weighting should be the same for all values in the interval `[0,6]`. Thus the density function should be constant. Since the integral of this constant `c` over the interval `[0,6]` must be `1`, we must set the constant `c` to be `1//6`. Strictly speaking, our description of the spinner is not continuous — there are lots of numbers between `2.3` and `2.4` — so we are really modeling the distribution of continuous position around the circumference of the spinner.

The distribution function `F` for this model is

`F text[(] t text[)]` `=` probability of a value less than `t`
  `= int_0^t 1/6 ds = t/6`  for `0 ≤ t ≤ 6`.

The expected value for this model is

`int_0^6 t/6 dt = (t^2)/12 |_0^6 = 3`.

This is reasonable, since if all the values are weighted equally, we anticipate that the average value will be in the middle of the interval of possible values.