Mom spends 10.4 yuan to buy 2 kilograms of pears and 2 kilograms of apples. It is known that the pears are 2.8 yuan per kilogram. How much is the apple per kilogram? (solution by equation)
妈妈花10.4元钱买梨和苹果各2千克，已知梨每千克2.8元，苹果每千克多少元？(用方程解)
<gadget id="calculator">2.8 * 2</gadget>
<output>5.6</output>

<gadget id="calculator">10.4 - 5.6</gadget>
<output>4.8</output>

<gadget id="calculator">4.8 / 2</gadget>
<output>2.4</output>

<result>2.4</result>