Mom bought 3 kilograms of apples for 20 yuan and got back 9.2 yuan. How much is an apple per kilogram?
妈妈拿20元买了3千克苹果，找回9.2元．每千克苹果多少元？
<gadget id="calculator">20 - 9.2</gadget>
<output>10.8</output>

<gadget id="calculator">10.8 / 3</gadget>
<output>3.6</output>

<result>3.6</result>