The product of two two-digit numbers is 3927. What is the sum of these two two-digit numbers?
有两个两位数的乘积是3927，这两个两位数的和是多少？
<gadget id="calculator">3 * 17</gadget>
<output>51</output>

<gadget id="calculator">7 * 11</gadget>
<output>77</output>

<gadget id="calculator">51 + 77</gadget>
<output>128</output>

<result>128</result>