Dad buys brown sugar and 1.5 kg of white sugar, and the total cost is 11.1 yuan. It is known that each kilogram of brown sugar is 3.2 yuan. How much is it per kilogram of sugar? (answer in two ways)
爸爸买红糖，白糖各1.5千克，共花11.1元，已知每千克红糖3.2元．每千克白糖多少元？(用两种方法解答)
<gadget id="calculator">3.2 * 1.5</gadget>
<output>4.8</output>

<gadget id="calculator">11.1 - 4.8</gadget>
<output>6.3</output>

<gadget id="calculator">6.3 / 1.5</gadget>
<output>4.2</output>

<result>4.2</result>