IlCreatore wrote:
A hunting lodge has enough fuel to keep 20 rooms heated for fourteen days. If the lodge decides to save fuel by turning off the heat in 5 unoccupied rooms, and each room requires the same amount of fuel to heat it, how many extra FULL days will the fuel supply last?
(A) 3
(B) 4
(C) 5
(D) 18
(E) 19
Let's assign some "nice" values to this scenario.
Let's say that we're heating the rooms with firewood, and it takes
1 log to heat the room for 1 day.
A hunting lodge has enough fuel to keep 20 rooms heated for 14 daysSo, heating 20 rooms would require 20 logs/day.
So, in 14 days, the NUMBER of logs the lodge need to burn = (20)(14) =
280 In other words, the lodge has
280 logs
...the lodge decides to save fuel by turning off the heat in 5 unoccupied rooms, and each room requires the same amount of fuel to heat itSo, we will heat only
15 rooms, and each room burns
1 log per day.
So, the number of DAYS the logs will last =
280/
15 =
18 2/3 How many extra FULL days will the fuel supply last?Answer =
18 2/3 days - 14 days = 4 2/3 days
The question asks for FULL days, so turning off the heat to 5 rooms will extend the fuel supply by 4 FULL days.
Cheers,
Brent