There are three cars A, B, and C, each driving from A to B at a certain speed. B starts 10 minutes later than C, and catches up with C 40 minutes after departure; A starts 10 minutes later than B, and after departure 60 minutes to catch up with C, how many minutes after A set off to catch up with B?
有甲、乙、丙三辆汽车，各以一定的速度从A地开往B地，乙比丙晚出发10分钟，出发后40分钟追上丙；甲比乙又晚出发10分钟，出发后60分钟追上丙，问甲出发后几分钟追上乙？
<gadget id="calculator">16 - 15</gadget>
<output>1</output>

<gadget id="calculator">10 / 1</gadget>
<output>10</output>

<gadget id="calculator">10 * 15</gadget>
<output>150</output>

<result>150</result>