There is a bunch of candies. On the first day, Xiao Li ate 10 yuan, on the second day he ate half of the remaining 5 pieces, and on the third day he ate another 10 yuan. It is known that the number of candies at the beginning is the last remaining 7 times lower. So how many pieces of candy are there in the beginning?
有一堆糖果，第一天，小李吃掉了10块，第二天吃掉了剩下的一半少5个，第三天又吃掉了10块，已知一开始糖果的数量是最后剩下的7倍．那么一开始有多少块糖果？
<gadget id="calculator">10 + 10</gadget>
<output>20</output>

<gadget id="calculator">7 - 1 - 1</gadget>
<output>5</output>

<gadget id="calculator">20 / 5</gadget>
<output>4</output>

<gadget id="calculator">4 * 7</gadget>
<output>28</output>

<result>28</result>