There are 128 black swans, and the number of white swans is 9 less than three times that of black swans. How many white swans are there?
黑天鹅有128只，白天鹅的只数比黑天鹅的3倍少9只．白天鹅有多少只？
<gadget id="calculator">128 * 3</gadget>
<output>384</output>

<gadget id="calculator">384 - 9</gadget>
<output>375</output>

<result>375</result>