Xiaohong and her two good friends go to the movies. If each movie ticket is priced at 21 yuan, how much will they have to pay in total?
小红和她的2个好朋友去看电影，如果每张电影票售价21元，她们一共要付多少元．
<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<gadget id="calculator">3 * 21</gadget>
<output>63</output>

<result>63</result>