Răspuns:
Explicație pas cu pas:
Ana |......|
Barbu |.......|.......|.......|.......| +1
Cosmin |.......|.......|.......|.......| +1 |.......|.......|.......|.......| +1 +2
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TOTAL 13 ori |.......| +1+1+1+2 = 148 timbre
13 ori |.......|= 148 -5
|.......| = 143 : 13
|.......|= 11
Deci :
Ana are 11 timbre
Barbu are 11*4+1= 45 timbre
Cosmin are 45*2+2= 92 timbre
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Total : 11+45+92 = 148 timbre
Succes !!!