Question

Fie numerele naturale consecutive pare a,b,c stiind ca a<b<iar b+a=18

Answer 1

a,a+2,a+4

b=a+2
c=a+4

b+a=18
a+2+a=18
2a=18-2
2a=16
a=16:2
a=8
b=8+2=10
c=8+4=12

Deci nr.sunt:8,10,12

Answer 2

a    /------------/
b    /------------/.2../        daca e par, are 2 in plus, suma lor fiind 18
      egalam segmentele
18-2=16  1 segm egale
cat e 1 segment sau a
16:2=8
cat e b?
8+2=10
cat e c?
10+2=12