Mom bought 1 watermelon and 2 apples after get off work, which cost 36 yuan in total. The boss said: "The price of this watermelon is exactly enough to buy 4 apples." How much does this watermelon cost?
妈妈下班买了1个西瓜和2个苹果，一共花了36元．老板说："这个西瓜的价钱正好可以买4个苹果．"这个西瓜要多少元．
<gadget id="calculator">4 + 2</gadget>
<output>6</output>

<gadget id="calculator">36 / 6</gadget>
<output>6</output>

<gadget id="calculator">6 * 4</gadget>
<output>24</output>

<result>24</result>