The mean of the minuend, the subtrahend and the difference is 60, the subtrahend is 3 times of the difference, what is the subtrahend.
被减数、减数与差的平均数是60，减数是差的3倍，减数是多少．
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">60 * (3/2)</gadget>
<output>90</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">90 * (3/4)</gadget>
<output>135/2 = around 67.5</output>

<result>135/2 = around 67.5</result>