A handkerchief is 1.3 yuan, and a towel is 0.7 yuan more expensive than a handkerchief. Ask: How much is it to buy 10 handkerchiefs and 20 towels?
一条手绢1.3元，一条毛巾比一条手绢贵0.7元，问：买10条手绢和20条毛巾，共用去多少钱？
<gadget id="calculator">1.3 * 10</gadget>
<output>13</output>

<gadget id="calculator">1.3 + 0.7</gadget>
<output>2</output>

<gadget id="calculator">2 * 20</gadget>
<output>40</output>

<gadget id="calculator">13 + 40</gadget>
<output>53</output>

<result>53</result>