Question

Un biciclist parcurge zilnic cu 25 km mai mult decat in ziua precedenta.In patru zile consecutive a parcurs 310 km.Aflati cati kilometri a parcurs in fiecare zi.

Answer 1

a=prima zi
b=a doua zi
c=a treia zi
d=a patra zi
a+b+c+d=310
b=a+25
c=b+25⇒c=a+50
d=c+25⇒d=a+75

a+b+c+d=310
a+a+25+a+50+a+75=310
4a+150=310
4a=160
a=40 km

b=a+25
b=40+25
b=65 km

c=b+25
c=65+25
c=90 km

d=c+25
d=90+25
d=115 km

Answer 2

x - drumul parcurs in prima zi
x + 25 - a2-a zi
x + 25 + 25 - a 3-a zi
x + 25 + 25 + 25 -a 4-a zi
x + x + 25 + x + 25 + 25 + x + 25 + 25 + 25 = 310
4x + 150 = 310
4x = 310 - 150
4x = 160
x = 160 : 4
x = 40 km in prima zi
40 + 25 = 65 km a 2-a zi
65 + 25 = 90 km a 3-a zi
90 + 25 = 115 a 4-a zi