What is the number that is 1.8 less than three times 2.74?
比2.74的3倍少1.8的数是多少．
<gadget id="calculator">2.74 * 3</gadget>
<output>8.22</output>

<gadget id="calculator">8.22 - 1.8</gadget>
<output>6.42</output>

<result>6.42</result>