Răspuns :
2dam=...m 40,0+
2dam=2x10m=20m 3,1
31dm=...m -----
31dm=31:10m=3,1m 43,1
20m+20m+3,1m=40m+3,1m=43,1m
43,1m=...dm
43,1=43,1x10dm=431dm
2dam=2x10m=20m 3,1
31dm=...m -----
31dm=31:10m=3,1m 43,1
20m+20m+3,1m=40m+3,1m=43,1m
43,1m=...dm
43,1=43,1x10dm=431dm