Question

Un om preistoric are cremene, scoici si melci, in total 3350. Cremenelesi scoicile sunt 1510, scoicile si melci sunt 2190. Cate bucati are fiecare?

Answer 1

Cremene+scoici=1510;
Scoici+melci=2190;
Cremene+melci+scoici=3350;
-Adunam:
=1510+2190=3350+scoici;
=3700=3350+scoici=
s=350
Cremene+350=1510=> cremene=1160.

350+melci=2190=> melci=1840.

Answer 2

c+s+m=3350
c+s=1510
s+m=2190
--------------------
c=? s=? m=?

1510+m=3350
m=3350-1510
m=1840 melci

c+2190=3350
c=3350-2190
c=1160 cremene

1160+s+1840=3350
s=3350-(1160+1840)
s=3350-3000
s=350 scoici

1160+350+1840=
=1510+1840
=3350