The sum of the two numbers A and B is 2007. If the number C is added, the average of these three numbers is 66 less than the average of the two numbers A and B. What should be the number C?
甲、乙两个数的和是2007，如果再加上丙数，这三个数的平均数比甲、乙两个数的平均数少66，丙数应该是多少．
<gadget id="calculator">2_007 / 2</gadget>
<output>2_007/2 = around 1_003.5</output>

<gadget id="calculator">(2_007/2) - 66</gadget>
<output>1_875/2 = around 937.5</output>

<gadget id="calculator">(1_875/2) * 3</gadget>
<output>5_625/2 = around 2_812.5</output>

<gadget id="calculator">(5_625/2) - 2_007</gadget>
<output>1_611/2 = around 805.5</output>

<result>1_611/2 = around 805.5</result>