Answer:
[tex]x= 15[/tex]
Step-by-step explanation:
Francisca's mistake was that when she had an equation [tex]5 = \frac{1}{3} x[/tex] instead of dividing both sides by [tex]\frac{1}{3}[/tex] she substracted [tex]\frac{1}{3}[/tex] from both sides. So the correct way would be...
[tex]5 = \frac{1}{3} x\\\\(5)(3) = (\frac{1}{3} x )(3)[/tex]
[tex]15 = x[/tex]
