Răspuns :

MFMid
x camasa
y cravata
x+y=180
x+x.10/100+y-y5/100=186
aducand la acelasi numitor 
110x+95y=18600
x=180-y
110.180-110y+95y=18600
15y=1200
y=80lei
x=100 lei
a+b = 180
1,1a+0,95b = 186
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inmultim prima ecuatie cu 1,1 si se scad1
1,1a+1,1b = 198
1,1a+0.95b = 186
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0,15b = 12 => b=80, a=100