If a number is divided by 2, 5, and 9 at the same time, the remainder is 1. What is the smallest number?
一个数同时被2、5、9除都余1，这个数最小是多少．
<gadget id="calculator">2 * 5 * 9</gadget>
<output>90</output>

<gadget id="calculator">90 + 1</gadget>
<output>91</output>

<result>91</result>