Now, we prepare a frequency distribution table

`{:("Interval"," Frequency"),("0.01-0.04"," 5"),("0.04-0.08"," 11"),("0.08-0.12"," 7"),("0.12-0.16"," 2"),("0.16-0.18"," 4"),("0.20-0.24"," 1"),(" Total"," 30"):}`

The total number of days for data, to prepare sulphur dioxide, n(S) = 30

The frequency of the sulphur dioxide in the interval `0.12-0.16,n(E)=2`

`therefore" Required probability"=(n(E))/(n(S))=(2)/(30)=(1)/(15)`