Hi,
Battery is 240 mAh (milli amperes x hours)
LED current is 2 mA (milli amperes; no hours!)
Ucontroller is 1 mA !
If this LED is ON for one hour, then it consumes 2 mAh.
To your calculation.
In 24 hours the ucontroller consumes 24h x 1mA = 24 mAh
Led is on for 100 s. One hour has 60 x 60 = 3600s. So 100s is 100/3600 h, that is about 0.03 h. The Led consumes about 0.06 mAh.
The controller needs 400 times the energy of the Led. Here you should optimize. Put the controller in power down mode as often as possible.
Hope this helps
Klaus