a driver just filled the car ' s gas tank with 18 liters of gasohol, a mixture consisting of 5 % ethanol and 95 % gasoline. if the car runs best on a mixture consisting of 10 % ethanol and 90 % gasoline, how many liters of ethanol must be added into the gas tank for the car to achieve optimum performance?
Pick one:  A) 1  B) 1.5  C) 1.8  D) 2.4  E) 3
<gadget id="calculator">18 * 5</gadget>
<output>90</output>

<gadget id="calculator">100 - 10</gadget>
<output>90</output>

<gadget id="calculator">90 / 90</gadget>
<output>1</output>

<result>A</result>
a driver just filled the car ' s gas tank with 18 liters of gasohol, a mixture consisting of 5 % ethanol and 95 % gasoline. if the car runs best on a mixture consisting of 10 % ethanol and 90 % gasoline, how many liters of ethanol must be added into the gas tank for the car to achieve optimum performance?
divide(multiply(18, 5), subtract(const_100, 10))
"let x be the number of liters of ethanol added to the gas tank . 0.05 ( 18 ) + x = 0.1 ( 18 + x ) 0.9 x = 1.8 - 0.9 x = 1 liter the answer is a ."