There are three piles of books, a total of 240 books. Heap A is 3 times more than Heap B by 30 books, and Heap C is 15 less than Heap B. So. How many books are there in A pile?
有三堆书，共240本．甲堆比乙堆的3倍多30本，丙堆比乙堆少15本．那么．甲堆书有多少本．
<gadget id="calculator">240 - 30</gadget>
<output>210</output>

<gadget id="calculator">15 + 210</gadget>
<output>225</output>

<gadget id="calculator">1 + 3 + 1</gadget>
<output>5</output>

<gadget id="calculator">225 / 5</gadget>
<output>45</output>

<gadget id="calculator">45 * 3</gadget>
<output>135</output>

<gadget id="calculator">135 + 30</gadget>
<output>165</output>

<result>165</result>