Cars A and B drive opposite each other, and the speed ratio is 7:8. When B reaches the midpoint, A is 24km away from the midpoint. Find the total length of the distance.
甲乙两车相对开出，速度比为7：8，当乙到中点时，甲离中点24km，求该路程的全长．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">7 / 8</gadget>
<output>7/8 = around 0.875</output>

<gadget id="calculator">(1/2) * (7/8)</gadget>
<output>7/16 = around 0.4375</output>

<gadget id="calculator">(1/2) - (7/16)</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">24 / (1/16)</gadget>
<output>384</output>

<result>384</result>