3 robinete si 7 pompe umplu un bazin 71hl intr-o ora , 3 robineti si 3 pompe umplu in bazin 39 hl intr-o ora . aflati cati litri curg printr-un robinet si cati litri curg printr-o pompa . metoda 3r............................7p ...................71 hl

Răspuns :

3r.....7p......71hl
3r.....3p......39hl
-----------------------
4p.......32
p=32:4
p=8

3r+3p=39
3r+24=39
3r=15
r=5
R:p=8
r=5