Detailed Instructions: You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.
See one example below:
Problem: From a pack of 52 cards, two cards are drawn together at random. What is the probability of both the cards being kings?

Option A:2/1223

Option B: 1/122

Option C: 1/221

Option D: 3/1253

Option E: 2/153

Solution: Option C
Explanation: Let s be the sample space.
Then n(s) = 52C2 = 1326
E = event of getting 2 kings out of 4
n(E) = 4C2 = 6
P(E) = 6/1326 = 1/221

Problem: Question: A motorcyclist started riding at highway marker A, drove 120 miles to highway marker B, and then, without pausing, continued to highway marker C, where she stopped. The average speed of the motorcyclist, over the course of the entire trip, was 40 miles per hour. If the ride from marker A to marker B lasted 3 times as many hours as the rest of the ride, and the distance from marker B to marker C was half of the distance from marker A to marker B, what was the average speed, in miles per hour, of the motorcyclist while driving from marker B to marker C?

Option A: 40

Option B: 45

Option C: 50

Option D: 55

Option E: 67.5
Solution:
Option E