There are 27 coins of 1 jiao and 5 jiao in Xiao Ming's piggy bank, worth 5.1 yuan. How many 5 jiao coins are there?
小明的储蓄罐里有1角和5角的硬币共27枚，价值5.1元．5角的硬币有多少枚．
<gadget id="calculator">5.1 * 10</gadget>
<output>51</output>

<gadget id="calculator">51 - 27</gadget>
<output>24</output>

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">24 / 4</gadget>
<output>6</output>

<result>6</result>