David installed a device on his car that guaranteed ti increase his gas mileage by 15%.he currently gets 22 per gallon. how much will the gas mileage increase after installing the device?

David installed a device on his car that guaranteed it increase his gas mileage by 15%.He currently gets 22 per gallon.
Question: How much will the gas mileage increase after installing the device?
=> 22 gas mileage per gallon is the current measure.
=> 15% is the increased after he installed a device on his car
=> 15% to be converted to decimals
=> 15% = .15
Solution
=> 22 * .15 = 3.3
=> 22 + 3.3 = 25.3 is the current mileage gas.