Question

in prima zi,un automobil a parcurs cu 70 km mai putin decit in a doua zi.In ziua a triea a parcurs cu 20 km mai mult decit in ziua a doua.In trei zile automobilul a parcurs in total 1300km.Ce distanta a parcurs in fiecare zi

Answer 1

notam zilele cu x, y si z
x+y+z=1300
x=y-70
z=y+20 
acum inlocuim
y-70+y+y+20=1300
3y-50=1300
3y=1300+50
3y=1350
y=1350:3
y=450
x=450-70=380
z=450+20=470

Answer 2

Fie prima zi -x , a 2-a zi -y , a 3-a zi - z
X= y-70
Z= y+20
 X+Y+Z = 1300
y-70 + y + 20+y = 1300
3y= 1300 + 70 - 20
y=450 (km) in a 2-a zi
x=450-70 = 380 (km) in 1 zi
z=450+20= 470 (km) in a 3-a zi