There are 20 fruits in the two bags. Take 7 fruits from the first bag and put them into the second bag. If the number of fruits in the two bags is the same, what is the original number of fruits in the first bag?
两袋水果共有20个，从第l袋取出7个水果放入第2袋，两袋中的水果个数相同，则第1个袋中原有水果多少个．
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 + 7</gadget>
<output>17</output>

<result>17</result>