The distance between A and B is 350 kilometers. Cars A and B drive from the two places at the same time. After 3.5 hours, the two cars meet. Car A travels 49 kilometers per hour. How many kilometers does Car B travel per hour? (answer in two ways)
甲乙两地相距350千米，甲、乙两车同时从两地相对开出，经过3.5小时后两车相遇，甲车每小时行49千米，乙车每小时行多少千米？(用两种方法解答)
<gadget id="calculator">49 * 3.5</gadget>
<output>171.5</output>

<gadget id="calculator">350 - 171.5</gadget>
<output>178.5</output>

<gadget id="calculator">178.5 / 3.5</gadget>
<output>51</output>

<result>51</result>