a+b=280-205
a+b=75
b-3/4=a aducem la acelasi numitor
4b-3=4a
a=(4b-3)/4
(4b-3)/4 +b =75 aducem la acelasi numitor
4b-3+4b=300
8b=300+3
8b=303
b=37,875
a=(4*37,875-3)/4= 148,5/4= 37,125
(3a+2b)/(205/41)=
(3*37,125+2* 37,875) supra 205/41
(111,375+75,75) supra 205/41=
187,125 supra 205/41
187,125= 187 intregi 125/1000= 187 intregi 1/8= 1497/8
1497/8 * 41/205= 61 377/1640= 37,425
