A and B brought a total of 80 yuan to the store to buy things. A used half of the money he brought to buy a comic book, and B spent 10 yuan to buy a tape. At this time, the money left by A is exactly three times that of B, so how much money does B bring?
甲、乙两人一共带了80元钱去商店买东西，甲用自己带的一半的钱买了一本漫画书，乙花了10元钱买了一盘磁带．这时甲剩下的钱恰好是乙剩下的3倍，那么乙带了多少元钱？
<gadget id="calculator">80 - 10</gadget>
<output>70</output>

<gadget id="calculator">6 + 1</gadget>
<output>7</output>

<gadget id="calculator">70 / 7</gadget>
<output>10</output>

<gadget id="calculator">10 + 10</gadget>
<output>20</output>

<result>20</result>