Răspuns :
a/b =5/7 ;a+b =60 ;a =60-b
60-b /b =5/7
7(60-b )=5b
420-7b =5b
12b =420
b =35
a =60-b
a=60-35 =25
a *b =25*35 =875
60-b /b =5/7
7(60-b )=5b
420-7b =5b
12b =420
b =35
a =60-b
a=60-35 =25
a *b =25*35 =875