Mom bought 3 towels and 3 cups in the mall, and spent a total of 21.6 yuan. Among them, each cup is 2.5 yuan, and how much is each towel? (solution with equation)
妈妈在商场买了3条毛巾和3个杯子，共花了21.6元．其中杯子每个2.5元，毛巾每条多少元？(用方程解答)
<gadget id="calculator">2.5 * 3</gadget>
<output>7.5</output>

<gadget id="calculator">21.6 - 7.5</gadget>
<output>14.1</output>

<gadget id="calculator">14.1 / 3</gadget>
<output>4.7</output>

<result>4.7</result>