A frog jumps up from the bottom of a 9-meter well. It takes 5 minutes for each jump of 3 meters, and then rests for 2 minutes. How many minutes does it take for the frog to jump from the bottom of the well to the mouth of the well?
青蛙从9米的井底往上跳，每跳3米要用5分钟，然后休息2分钟．那么青蛙从井底跳到井口要用多少分钟？
<gadget id="calculator">9 / 3</gadget>
<output>3</output>

<gadget id="calculator">5 + 2</gadget>
<output>7</output>

<gadget id="calculator">3 * 7</gadget>
<output>21</output>

<gadget id="calculator">21 - 2</gadget>
<output>19</output>

<result>19</result>