For this case we must make a conversion. We have that by definition 1 liter equals 0.264172 gallons.
So, making a rule of three we have to:
1L ----------------> 0.264172 gallons
15L --------------> x
Where:
x: Represents gallons equivalent to 15 liters.
[tex]x = \frac {15 * 0.264172} {1}\\x = 3.96258[/tex]
Rounding out we have that 15 liters equals 3.96 gallons.
Answer:
3.96 gallons
