Huanhuan, Yingying, and Beibei each bought a birthday present for their mother, and agreed to combine the purchases of the three gifts and share them equally. If the gift purchased by each person has been paid by himself, then Huanhuan paid 1 yuan more, Yingying paid 3 yuan less, and Beibei paid 20 yuan. How much is the sum of these three gifts?
欢欢、迎迎和贝贝每人为他们的妈妈购买了一份生日礼物，并且商定把购买这三份礼物的款数合起来，由三人平均负担．如果每人购买的礼物已经由本人付款，那么欢欢多付了1元，迎迎少付了3元，而贝贝付了20元．这三份礼品款数的总和是多少元？
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">20 - 2</gadget>
<output>18</output>

<gadget id="calculator">18 * 3</gadget>
<output>54</output>

<result>54</result>