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.

[EX Q]: Question: A certain electric-company plan offers customers reduced rates for electricity used between 8 p.m. and 8 a.m. weekdays and 24 hours a day Saturdays and Sundays. Under this plan, the reduced rates Z apply to what fraction of a week?

 Option A:  1/2

 Option B:  5/8

 Option C:  9/14

 Option D:  16/21

 Option E:  9/10
[EX A]: Option C

[EX Q]: Question: Rahim bought 4 pillows with the average cost of $5. If Rahim also buys the fifth pillow with the price of $ 10, what is the average (arithmetic mean) price of those 5 pillows?

 Option A: $6

 Option B: $5

 Option C: $5.5

 Option D: $6.5

 Option E: $7
[EX A]: Option A

[EX Q]: Question: A money lender lent Rs. 1000 at 3% per year and Rs. 1400 at 5% per year. The amount should be returned to him when the total interest comes to Rs. 350. Find the number of years.

 Option A: 3.5

 Option B: 3.75

 Option C: 4

 Option D: 4.25

 Option E: 4.5
[EX A]:
Option A