The ratio of the number of table tennis balls in the red, yellow, and blue bags is 4:2:3. If you put 30 table tennis balls in the red bag into the blue bag, and at the same time take some from the yellow bag to the blue bag, then The ratio of the number of table tennis balls in the red, yellow, and blue bags is 2:1:3, how many table tennis balls are taken from the yellow bag to the blue bag?
红、黄、蓝三个袋中乒乓球个数比为4：2：3，如果把红袋中乒乓球放30个到蓝袋中，同时从黄袋中拿一些到蓝袋中，这时红、黄、蓝三个袋中乒乓球个数比为2：1：3，从黄袋中拿多少个乒乓球到蓝袋中的？
<gadget id="calculator">4 + 2 + 3</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">2 + 1 + 3</gadget>
<output>6</output>

<gadget id="calculator">2 / 6</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(4/9) - (1/3)</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">30 / (1/9)</gadget>
<output>270</output>

<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">270 * (2/9)</gadget>
<output>60</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">270 * (1/6)</gadget>
<output>45</output>

<gadget id="calculator">60 - 45</gadget>
<output>15</output>

<result>15</result>