If your asking how much money he has left, all we have to do is subtract $0.79 and $1.76 from $20.56
To make it easier, we can just add $0.79 and $1.76 then subtract that number from $20.56
$1.76 + $0.79 = $2.55
Now we can subtract $2.55 from $20.56
$20.56 - $2.55 = $18.01
Therefore, he has $18.01 left
Hope this helps you
-AaronWiseIsBae