Multiple Choice Identify the
choice that best completes the statement or answers the question.


1.

Which equation shows that z is directly proportional to the square root
of x and inversely proportional to the cube of y?


2.

The volume of a gas varies directly as its temperature and inversely as its
pressure. Alison is working with a gas in a laboratory at Lynchburg College. At a temperature of 375
Kelvin and a pressure of 25 pascals, she measured the volume of this gas as 30 cubic centimeters.
What volume should she expect if she decreases the temperature to 320 Kelvin and increases the
pressure to 40 pascals?
a.  4 cm^{3}  c.  16 cm^{3}  b.  8 cm^{3}  d.  46.875
cm^{3} 


3.

The current in a simple electrical circuit varies inversely as the resistance.
Ryan is studying electronic technology at Norfolk State College. In one of his labs, he measured a
current of 45 amps in a circuit when the resistance was 6 ohms. What will be the current in this
circuit if the resistance is 10 ohms?
a.  27 amps  c.  49 amps  b.  41 amps  d.  75 amps 


4.

The frequency of a vibrating string varies inversely as its length. If a piano
string that is 30 inches long vibrates at 200 cycles per second, what would be the frequency of a
string that is 48 inches long?
a.  1,500 cycles per second  c.  125 cycles per
second  b.  175 cycles per second  d.  75 cycles per second 


5.

The illumination produced by a light source varies inversely as the square of
the distance from the source. If the illumination from a lamp at a distance of 6 meters is 50
candela, what is the illumination at a distance of 10 meters from the lamp?
a.  88 candelas  c.  30 candelas  b.  54
candelas  d.  18
candelas 


6.

The time it takes to travel a certain distance is inversely proportional to the
average speed for the trip. It took Tran 3 hours to drive from Richmond to Roanoke, a distance of 186
miles. Heavier traffic on his return trip resulted in an average speed that was 8 miles per hour
slower than that for this trip to Roanoke. About how much longer did the return trip take than
the trip to Roanoke?
a.  12 min  c.  44 min  b.  27 min  d.  62 min 


7.

The amount of time needed to mow the grass in a city park varies directly as the
area to be mowed and inversely as the number of workers. If it takes 2 hours for 3 workers to mow
150,000 square feet, how long will it take for 5 workers to mow 225,000 square feet?
a.  54 min  c.  2 h 30 min  b.  1 h 48 min  d.  3 h 
