Respuesta :

[box] equals 1/2 (i think; check by dividing 0.8 by 0.4 on calculator, or 4/5 divided by 2/5 on fraction calculator... kind of obvious)
4/5* x= 2/5
⇒ x= 2/5/ (4/5)
⇒ x= 2/5* (5/4)
⇒ x= 1/2

Final answer: x=1/2~