There are 45 black and white pieces in total. If 1/3 of the black pieces and 5 white pieces are taken away, the number of black and white pieces is equal. It turns out how many sunspots there are.
黑、白两种棋子一共有45颗，如果拿走黑子的(1/3)和5颗白子后，黑、白棋子数相等．原来有黑子多少颗．
<gadget id="calculator">45 - 5</gadget>
<output>40</output>

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

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 + (2/3)</gadget>
<output>5/3 = around 1.666667</output>

<gadget id="calculator">40 / (5/3)</gadget>
<output>24</output>

<result>24</result>