जिंदगी में शादी के अलावा ट्रेन में RAC ही एक ऐसी स्थिति है,जिसमें दो अजनबी साथ निभाने को मजबूर होते है। - Junaid

Yes that may be true ,

1560 must have some taxes included in it.
And the discount is only on ticket base price ,not on taxes.

And...
more...

this holds true for my other ticket on 1 August in second AC From Rewari to Jamnagar

The ticket base price is 2000 and 99.80 rs tax= 2100

For current ticket ,discount will be 2000*0.1=200

So base ticekt price will be 1800 +100 (for tax)=1900
and the same is ticket price for current in Second AC from rewari to Jamnagar .