Question

Din 25 de elevi ai clasei a V a B16 elevi joaca handbal,13 elevi tenis, iar 2 nu fac sport deloc.Cati elevi practica ambele sporturi?

Answer 1

h+t+2+x=25 elevi
h=16
t=13
nu fac sport 2
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x=? (t+h)

(16+13+2)-x=25 elevi
x=31-25
x=6 elevi fac si hambal si tenis

16-6=10elevi fac doar hambal
13-6=7 elevi joaca doar tenis
6 elevi fac si hambal si tenis
2 elevi nu fac sport

10+7+6+2=25 elevi in clasa

Answer 2

25-2=23
13+16=29
29-23=6 elevi practica ambele sporturi