Question

a=75% din b
a+b=4,(6)
a=?
b=?

Answer 1

A=75 din B⇒A= \frac{3}{4} B⇒4A=3B \left \{ {{4A=3B} \atop {A+B=4,6}} \right. ⇒  \left \{ {{4(B-4,6)=3B} \atop {A=B-4,6}} \right. ⇒ \left \{ {{4B-18,4=3B} \atop {A=B-4,6}} \right.⇒ \left \{ {{B=18,4} \atop {A=18,4-4,6}} \right. ⇒ \left \{ {{B=18,4} \atop {A=13.8}} \right.