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 car traveled 75% of the way from Town A to Town B at an average speed of 75 mph. The car traveled at an average speed of v mph for the remaining part of the trip. The average speed for the entire trip was 50 mph. What is v in mph?

 Option A: 30

 Option B: 35

 Option C: 25

 Option D: 40

 Option E: 45
Option C

Question: Find the number of ways of arranging the letters of the word "MATERIAL" such that all the vowels in the word are to come together?

 Option A: 1887 ways

 Option B: 1440 ways

 Option C: 1657 ways

 Option D: 1652 ways

 Option E: 6745 ways
Option B

Question: A sum of Rs.4300 is invested at a compound interest for three years, the rate of interest being 10% p.a., 20% p.a. and 25% p.a. for the 1st, 2nd and the 3rd years respectively. Find the interest received at the end of the three years.

 Option A: Rs.2520

 Option B: Rs.3120

 Option C: Rs.3320

 Option D: Rs.2795

 Option E: None of these

Option D