Notam:
n = numarul total al copiilor de la club
practica fotbal:
2n/6
practica inotul:
n/6
practica atletismul:
72
2n/6 + n/6 + 72 = n |×6
2n + n + 72 × 6 = 6× n
6×n - 3×n = 432
3×n = 432
n = 432 : 3
n = 144 (copii)
Verificare:
2×144/6 + 144/6 + 72 =
= 2 × 24 + 24 + 72 =
= 48 + 24 + 72 =
= 144
/ = fractie
