13)a+b+c+d=588 a=!___! b=!___!+2 c=!___!+4 d=!___!+6 588-(2+4+6)=576 576:4=144-primul nr (a) 144+2=146-al doilea nr (b) 144+4=148-al treilea nr(c) 144+6=150-al patrulea nr d P:144+146+148+150=588
17)G+R+V=2 457-beculete G=!___! R=!___!+243 V=!___!+243+243 2 457-(243+243+243)=2457-729 1728:3=576-beculete galbene G 576+243=819-beculete rosii R 819+243=1 062 beculete verzi V P:576+819+1 062=2457