Răspuns :
notam nr. necunoscut cu x si rescriem problema matematic:
3*x+123=1/4(x+91) <=>3*x-1/4*x=123+91/4, aducem la acelasi numitor
=>(12*x-x)/4=(4*123+91)/4 |*4 =>11*x=583 =>x=53
3*x+123=1/4(x+91) <=>3*x-1/4*x=123+91/4, aducem la acelasi numitor
=>(12*x-x)/4=(4*123+91)/4 |*4 =>11*x=583 =>x=53
3x-123= (x+91):4
4*(3x-123)=x+91
12x-492= x+91
12x-x=492+91
11x=583
x=583:11
x=53
4*(3x-123)=x+91
12x-492= x+91
12x-x=492+91
11x=583
x=583:11
x=53