Question

intr o scoala sunt inscrisi in cls a1,2,3,4. 429 elevi. In cls a1,2,3 sunt 296 iar in a3,4 sunt 204 elevi.câti elevi sunt inscrisi in fiecare clasa daca a1,2 este un numar egal de elevi?

Answer 1

a+b+c+d=429
a+b+c=296
c+d=204
d=429-296=133
c=204-133=71
a=b  atunci a+a+c=296   2a+71=296   2a=296-71=225  a=225:2=112rest1

Answer 2

clasa1=a
clasa2=b
clasa3=c
clasa4=d
a+b+c+d=429
a+b+c=296
c+d=204

a+b+c+d=429
a+b+c=296=>d=429-296=>d=143

c+d=204=>c+143=204
=>c=204-143=>c=61

a=b=x

a+b+c=296=>a+b+61= 296=>a+b=296-61=>
2x=235=>x=117,5=>
a=117,5
b=117,5