Question

500 ml + 0,20 litros + 320 cm³ = ?

Answer 1

500ml = 500cm³  --> = 0,5L
0,20 L
320cm³= 0,32L

0,5+0,2+0,32= 0,7+0,32=1,02Litros

Answer 2

1 ml = 1 cm³
1 l = 1000 ml = 1000 cm³
_________________

$500~ml+0,20~l+320~cm^{3}=500~cm^{3}+(0,20\cdot1000~cm^{3})+320~cm^{3}\\500~ml+0,20~l+320~cm^{3}=820~cm^{3}+200~cm^{3}\\\\\boxed{\boxed{500~ml+0,20~l+320~cm^{3}=1020~cm^{3}}}$