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.

Question: A group of hikers is planning a trip that will take them up a mountain using one route and back down using another route. They plan to travel down the mountain at a rate of one and a half times the rate they will use on the way up, but the time each route will take is the same. If they will go up the mountain at a rate of 8 miles per day and it will take them two days, how many miles long is the route down the mountain?

 Option A: 18

 Option B: 20

 Option C: 22

 Option D: 24

 Option E: 25
Option D

Question: Pipe A can fill a tank in 16 minutes and pipe B cam empty it in 24 minutes. If both the pipes are opened together after how many minutes should pipe B be closed, so that the tank is filled in 30 minutes?

 Option A: 20

 Option B: 16

 Option C: 24

 Option D: 28

 Option E: 21
Option E

Question: Lavanya can read a book in L minutes. What part of the book can he read in 10 minutes?(L>10)

 Option A: (k - 8

 Option B: 10/L

 Option C: 8 + k

 Option D: k-8

 Option E: 8/k

Option B