The car departed from the school to play in Taihu Lake, and drove (3/4) the whole way in (6/7) hours. At this time, it was still 4 kilometers away from Taihu Lake. At this speed, how many hours will it take to complete the journey?
汽车从学校出发到太湖玩，(6/7)小时行驶了全程的(3/4)，这时距太湖边还有4千米．照这样的速度，行完全程共用多少小时？
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">6 / 7</gadget>
<output>6/7 = around 0.857143</output>

<gadget id="calculator">(3/4) / (6/7)</gadget>
<output>7/8 = around 0.875</output>

<gadget id="calculator">1 / (7/8)</gadget>
<output>8/7 = around 1.142857</output>

<result>8/7 = around 1.142857</result>