When Xiao Ming calculates "40+□*5", he does the addition first and then the multiplication, and the result is 800. What is the correct number for this question.
小明在计算"40+□*5"时，先算加法，后算乘法，得到的结果是800．这道题的正确得数是多少．
<gadget id="calculator">800 / 5</gadget>
<output>160</output>

<gadget id="calculator">160 - 40</gadget>
<output>120</output>

<gadget id="calculator">120 * 5</gadget>
<output>600</output>

<gadget id="calculator">40 + 600</gadget>
<output>640</output>

<result>640</result>