Answer:
Step-by-step explanation:
13.3 + 6.7 = 20
[tex]\frac{13.3}{20} = \frac{x}{x + 10} \\\\ 20x = 13.3(x + 10) \\\ 20x = 13.3x + 133 \\\ 20x - 13.3x = 133 \\\ 6.7x = 133 \\\ x = \frac{133}{6.7} \\\\ x ≈ 19.85 \\\ x ≈ 20[/tex]
I hope I've helped you.