STEP - BY - STEP EXPLANATION
What to find?
The cost of painting a ceiling of a room of 12m² .
Given:
Area of the ceiling to paint =12m²
Cost of painting 5.32m² = 9 eur.
Step 1
Let x be the cost of painting a ceiling of room 12m².
Using propotion to solve;
9 euro = 5.32m²
x = 12m²
Step 2
Cross - multiply.
[tex]5.32\times x=9\times12[/tex][tex]5.32x=108[/tex]Step 3
Divide both-side of the equation by 5.32.
[tex]\frac{5.32x}{5.32}=\frac{108}{5.32}[/tex][tex]x=20.3[/tex]ANSWER
Cost of painting the ceiling of a room of 12m² is 20.3 eur
