Li Dong's father rode a motorcycle from A to B for errands, traveling 46 kilometers per hour. After 2.5 hours, he traveled exactly half of the way. Due to time constraints, he speeded up and traveled 4 kilometers per hour more than before. How many hours will it take him to reach B?
李东的爸爸骑摩托车从甲地去乙地办事，每小时行46千米，行了2.5小时后，恰好行完全程的一半．因时间紧迫，他加快了速度，每小时比原来多行4千米．他还要用多少小时才能到达乙地？
<gadget id="calculator">46 + 4</gadget>
<output>50</output>

<gadget id="calculator">2.5 / 50</gadget>
<output>0.05</output>

<gadget id="calculator">46 * 0.05</gadget>
<output>2.3</output>

<result>2.3</result>