The distance between A and B is 90 meters. It takes 30 seconds for the bun to go from A to B, and 15 seconds for the pineapple to go from B to A. Now the bun and the pineapple are walking opposite each other from A and B at the same time. What is the distance in meters from point B?
A、B两地相距90米，包子从A地到B地需要30秒，菠萝从B地到A地需要15秒，现在包子和菠萝从A、B两地同时相对而行，相遇时包子与B地的距离是多少米．
<gadget id="calculator">90 / 30</gadget>
<output>3</output>

<gadget id="calculator">90 / 15</gadget>
<output>6</output>

<gadget id="calculator">3 + 6</gadget>
<output>9</output>

<gadget id="calculator">90 / 9</gadget>
<output>10</output>

<gadget id="calculator">10 * 6</gadget>
<output>60</output>

<result>60</result>