The sum of 3 consecutive odd numbers is 87, what is the smallest of these three numbers?
3个连续的奇数的和是87，这三个数最小是多少．
<gadget id="calculator">87 / 3</gadget>
<output>29</output>

<gadget id="calculator">29 - 2</gadget>
<output>27</output>

<result>27</result>