How many two-digit decimals are there that are greater than 0.5 and less than 0.7?
大于0.5小于0.7的两位小数有多少个．
<gadget id="calculator">69 - 51</gadget>
<output>18</output>

<gadget id="calculator">18 + 1</gadget>
<output>19</output>

<result>19</result>