Bonsoir;

1)

350g = 0,35kg

4,5hg = 0,45kg

20,3dag = 0,203kg

masse totale:

0,35+1,245+0,45+0,203

=>2,248kg

2)

135hl = 13 500L

9L -> 1kg

1L -> 1/9

13 500L -> 13500/9

=> 1 500 fromages