Cat

Half of the rest postpone a new smartphone for one-fifth of the monthly pocket money contributed to Maros for food for his cat. The remaining € 8 is spent. How much pocket money gets Maros a month?

Correct answer:

x =  20 Eur

Step-by-step explanation:

$$\begin{gathered} \frac{1}{5}x+\frac{1}{2}\cdot (1-\frac{1}{5})x+8=x \\ 1/5\cdot x+1/2\cdot (1-1/5)\cdot x+8=x \\ 4x=80 \\ x=\frac{80}{4}=20 \\ x=20=20\text{Eur} \end{gathered}$$

Try another example