Question

ex 6 si 7 repede va rog, ajutor

Answer 1

6)

X=pretul initial (adica 100%) ...
a).
      (x * 160/100) * 130/100 = 182 (lei)

       x =
$\frac{182 \times 100 \times 100}{160 \times 130}$
X=87,5 lei
b).
       87,5/182 = p/100  de
unde 
P~48/100

7)
$\frac{4x - 2y}{2x - y} = \frac{1}{4}$
16x-8y=2x-y
16x-2x= - y+8y
14x=7y
$\frac{x}{y} = \frac{7}{14} \div |7| = \frac{1}{2}$