Question

Suma unui elev este o data si jum. cat suma celui de-al doilea elev,a carui suma e o data si jum. celui de al treilea elev.
Sa se afle suma fiecaruia daca in total au 38 de lei.(E urgent)

Answer 1

a+b+c=38
a=b+b:2
b=c+c:2
b+b:2+c+c:2+c=38
c+c:2+(c+c:2):2+c+c:2+c=38
4×c+(c+c:2):2=38/×2
8×c+c+c:2=76/×2
16×c+2c+c=152
19c=152:19=8
b=8+8:2=12
a=12+12:2=12+6=18