In a subtraction formula, the sum of the minuend, the subtrahend and the difference is 400, and the difference is 4 times the subtrahend. How much is the difference.
在一道减法算式里，被减数、减数与差的和是400，差是减数的4倍．差是多少．
<gadget id="calculator">1 + 4 + 1 + 4</gadget>
<output>10</output>

<gadget id="calculator">400 / 10</gadget>
<output>40</output>

<gadget id="calculator">4 * 40</gadget>
<output>160</output>

<result>160</result>