Robert earned a commission of $23600 x 10/100 = $<<23600*10/100=2360>>2360.
So, he earned a total of $1250 + $2360 = $<<1250+2360=3610>>3610.
And, he saved $3610 x 20/100 = $<<3610*20/100=722>>722.
Therefore, his total expenses last month was $3610 - $722= $<<3610-722=2888>>2888
#### 2888