Răspuns :
a) a+2b+c= a+b+b+c= 24+5=29
b) 2a+5b+3c= 2a+2b+3b+3c= 2( a+b)+ 3(b+c)= 2 x 24+ 3 x 5= 48+15= 63
c) 3a+7b+4c= 3a+3b+4b+4c= 3(a+b)+ 4(b+c)= 3 x 24+ 4 x 5= 72+ 20= 92
b) 2a+5b+3c= 2a+2b+3b+3c= 2( a+b)+ 3(b+c)= 2 x 24+ 3 x 5= 48+15= 63
c) 3a+7b+4c= 3a+3b+4b+4c= 3(a+b)+ 4(b+c)= 3 x 24+ 4 x 5= 72+ 20= 92