Xiaomei plays the game of blowing bubbles, blowing once a minute, exactly 60 bubbles are blown each time, after the bubbles are blown, (1/2) of the bubbles burst after 1 minute, and (1/2) after 2 minutes /30) bubbles did not burst, after 2.5 minutes all the bubbles burst. Then, when Xiaomei blows out the bubbles for the 30th time, how many bubbles are there that are not broken?
小美玩吹泡泡的游戏，每分钟吹1次，每次恰好吹出60个泡泡，泡泡吹出后，经过1分钟有(1/2)的泡泡破了，经过2分钟有(1/30)的泡泡没有破，经过2.5分钟泡泡全破了．那么，小美在第30次吹出泡泡的时候，没有破的泡泡共有多少个．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 + (1/2) + (1/30)</gadget>
<output>23/15 = around 1.533333</output>

<gadget id="calculator">60 * (23/15)</gadget>
<output>92</output>

<result>92</result>