38 iaurt......14smantana.....132lei
36iaurt 7 smantana 100lei /*2
=========================
38 iaurt 14 smantana 132lei
72iaurt 14 smanatan 200lei
===========================scadem din a doua ecuatie prima ecuatie
34 iaurt 68lei
1 iaurt=68/34=2lei
38*2+14 smantana=132
76+14 smantana=132
i pahar smantana=132-76)/14=56/14=4lei
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