The cruise ship goes down the current at 7 kilometers per hour, and goes upstream at 5 kilometers per hour. Two cruise ships depart from the same place at the same time, one goes down the current and then returns; the other goes upstream and then returns. As a result, they returned to the starting point at the same time after 1 hour, ignoring the turning time of the bow. For how many minutes during this 1 hour are the two ships heading in the same direction?
游船顺流而下，每小时前进7公里，逆流而上，每小时前进5公里．两条游船同时从同一个地方出发，一条顺水而下，然后返回；一条逆流而上，然后返回．结果，1小时以后它们同时回到出发点，忽略船头掉头时间．在这1小时内有多少分钟这两条船的前进方向相同？
<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">(5/7) * 60</gadget>
<output>300/7 = around 42.857143</output>

<gadget id="calculator">1 + (5/7)</gadget>
<output>12/7 = around 1.714286</output>

<gadget id="calculator">(300/7) / (12/7)</gadget>
<output>25</output>

<gadget id="calculator">35 - 25</gadget>
<output>10</output>

<result>10</result>