Question 1

An older dormitory on campus is notorious for its poorly maintained plumbing. In addition to other problems, sink and shower faucets in the dorm’s bathrooms seem to drip constantly. Equipped with small measuring cups, you and a number of friends who live in the dorm check each faucet in the dorm one night and measure how much water each leaky one dribbles out in a minute. You find 25 drippy faucets, and they leak an average of one tablespoon of water per minute (about one drip every second, incidentally). If the 25 drippy faucets are not repaired, how many gallons of water will they collectively waste during the next 30 days, assuming they all drip around the clock at a rate of one tablespoon per minute?

TOTAL TABLESPOONS = 25 faucets X 30 days X 24 hours per day X 60 minutes per hour

TOTAL TABLESPOONS = 1,080,000

TOTAL OUNCES= 1,080,000 / 2 (540,000)

TOTAL PINTS = 540,000 / 16 (33,750)

TOTAL QUARTS = 33,750 / 2 (16,875)

TOTAL GALLONS = 16,875 / 4 (4,218.75)

4,219 gallons

5,556 gallons

6,991 gallons

7,383 gallons

Question 2

After the third break-in this year at a ground-level computer lab in the university’s science building, campus security officials have announced that they will leave the lab’s lights on when the lab is not in use as part of an effort to deter additional burglaries. Several faculty members and students have denounced the plan as wasteful, considering the amount of electricity the lab’s lights will consume. The lab is lit by 40 fluorescent light fixtures, each containing two 40-watt tubes. The lab closes at 9 p.m. and reopens at 8 a.m. Monday through Friday. It is closed on Saturdays and Sundays. If the university pays 8.59 cents per kilowatt hour of electricity it uses, what will be the weekly cost in dollars of keeping the lab’s lights on during the hours the lab is closed?

HOURS VACANT = 11 X 5 + 48 (103)

TOTAL WATTS = 40 X 40 X 2 (3,200)

TOTAL WATT HOURS = 103 X 3,200 (329,600)

TOTAL KILOWATT HOURS = 329,600 / 1,000 (329.6)

TOTAL COST = 329.6 kilowatt hours X .0859 cents per kilowatt hour

TOTAL COST = $28.31264

$6.36

$15.56

$28.31

$34.75

Question 3

Each day, the campus library dumps all scrap paper generated in the building into a Dumpster measuring 12 feet long, 8 feet wide, and 4 feet deep. Most of the scrap is from copy machines. Last semester, the library filled the Dumpster 20 times during the semester, or a little more than once a week. How many cubic feet of scrap paper did the library produce last semester?

VOLUME = WIDTH X LENGTH X HEIGHTH

VOLUME = 8 feet X 12 feet X 4 feet

VOLUME = 384 cubic fee

SEMESTER VOLUME = 384 cubic feet X 20

SEMESTER VOLUME = 7,680 cubic feet

4,515 cubic feet

5,671 cubic feet

6,395 cubic feet

7,680 cubic feet