Question

suma a 3 nr este 7889. daca dublam primul numar il obtinem pe al 2 care este de 974 mai mic decit al 3. Care este peimul nr?

Answer 1

a+-b+c=7889
2a=b
b=c-974    c=b+974=2a+974
a+2a+2a+974=7889
5a=7889-974
5a=6915
a=1383
b=2a=1383*2=2766
c=2766+974=3740

Answer 2

a+b+c=7889
2a=b
b=c-974⇒2a=c-974⇒c=2a+974
a+2a+2a+974=7889
5a+974=7889
5a=7889-974
5a=6915
a=6915:5
a=1383
b=2a
b=2*1383
b=2766
c=2a+974
c=2*1383+974
c=3740
V:1383+2766+3740=7889