208)
$(-15-2)-(-3+7)+(-11+6)+(3-4)-(-27)=$
$=-17-4-5-1+27=$
$=-17-4-5-1+27=0$
209)
$-18-(-5-7)+(9-4)-(+3+2)=$
$=-18-(-12)+5-5=$
$=-18+12+5-5=-6$
210)
$11-(18+7-14)-(10-2)+(8-3)-(6-3)=$
$=11-11-8+5-3=-6$
Magari riuscissi a leggerle!