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: If one-third of one-fourth of a number is 15, then three-tenth of that number is

Option A: 35

Option B: 36

Option C: 45

Option D: 54

Option E: 57
Option D

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
Option C

Question: A certain number of workers can do a work in 85 days. If there were 10 workers more it could be finished in 10 days less. How many workers are there?

Option A: 75

Option B: 30

Option C: 28

Option D: 24

Option E: 32
Option A