Respuesta :

432:20 = x:1

20x = 432

x = 21.6

On 1 gallon of gas, he can drive 21.6 miles.

Brainliest? :)) ♡´・ᴗ・`♡
Make your equation:

[tex] \frac{432}{20} = x[/tex]

Which is
[tex] \frac{miles}{gallons} [/tex]
Solve for x:

[tex]x = 21.6[/tex]