Question

O mașină parcurge in prima zi 35%din drum. A doua zi 20% din rest, iar a treia zi restul de 624 km. Aflați Cati km are drumul in total?

Answer 1

x=tot drumul
Prima zi:(35:100)×x
x-[(35:100)×x)=
(100x-35x):100=
(65x):100 (a ramas)
A doua zi: (20:100)×[(65x):100]=
(1300x):10000
A treia zi : 624
x-[(35x):100]-[(1300x):10000]=624
(10000x-3500x-1300x):10000=624
(5200x):10000=624
5200x=624×10000
5200x=6240000
x=6240000:5200
x=1200km