When Xiaoqiang calculated 420-□*3, he did the subtraction first, and the result was 930. So what is the correct answer for this question?
小强在计算420-□*3时先算了减法，结果得出930．那么这道题的正确结果应该是多少．
<gadget id="calculator">930 / 3</gadget>
<output>310</output>

<gadget id="calculator">420 - 310</gadget>
<output>110</output>

<gadget id="calculator">110 * 3</gadget>
<output>330</output>

<gadget id="calculator">420 - 330</gadget>
<output>90</output>

<result>90</result>