from such link

https://www.google.com/search?q=three-digit+integer

let's assume that the 3-digit random number is 673, with normal distribution parameters: expectation = 104 and standard deviation = 985,

then the normal distribution value from MS Excel is

either

0.718255 =NORM.DIST(673,104,985,TRUE)

or

0.000343 =NORM.DIST(673,104,985,FALSE)

where the first one is coming from the cdf and the second comes from the pdf, and

you may calculate the second one in google as well

https://www.google.com/search?q=1%2Fsqrt%282*pi%29%2F985*exp%28-%28673-104%29%5E2%2F2%2F985%5E2%29

= 0.0003427776

Calculate with the help of this neat Normal Distribution Applet/Calculator:

https://homepage.divms.uiowa.edu/~mbognar/applets/normal.html