Răspuns :
a+b+c=6986
notam cu x partea egala a celor 3 nr.
a-215=x
a=x+215
b-431=x
b=x+431
c-352=x
c=x+352
x+215+x+431+x+352=6986
3x+998=6986
3x=6986-998
3x=5988
x=5988/3
x=1996
a=1996+215
a=2211
b=x+431
b=1996+431
b=2427
c=x+352
c=1996+352
c=2348
verificare:
2211+2427+2348=6986
notam cu x partea egala a celor 3 nr.
a-215=x
a=x+215
b-431=x
b=x+431
c-352=x
c=x+352
x+215+x+431+x+352=6986
3x+998=6986
3x=6986-998
3x=5988
x=5988/3
x=1996
a=1996+215
a=2211
b=x+431
b=1996+431
b=2427
c=x+352
c=1996+352
c=2348
verificare:
2211+2427+2348=6986
a-215=x
a=x+215
b-431=x
b=x+431
c-352=x
c=x+352
x+215+x+431+x+352=6986
3x+998=6986
3x=6986-998
3x=5988
x=5988/3
x=1996
a=1996+215
a=2211
b=x+431
b=1996+431
b=2427
c=x+352
c=1996+352
c=2348
a=x+215
b-431=x
b=x+431
c-352=x
c=x+352
x+215+x+431+x+352=6986
3x+998=6986
3x=6986-998
3x=5988
x=5988/3
x=1996
a=1996+215
a=2211
b=x+431
b=1996+431
b=2427
c=x+352
c=1996+352
c=2348