Respuesta :

FLORC
12+4+9+13+7+11+5+2+_+_ /10= 8
x10 both sides

12+4+9+13+7+11+5+2+_+_=80
63+_+_=80
-63 both sides
_+_= 17
any two numbers that add up to 17 can go in the planks
7,10
RELAXING NOICE
Relax