MATHEMATICAL LENS
Roller Coasters and Railways
1. Expedition 〖 Everest〗^TM (see photo graph 1) is popular and
thrilling roller coaster ride at Disney’s Animal Kingdom
theme park, Walt Disney World Resort, in Orlando, Florida.
To the disappointment of many young visitors to the park.
however, this roller coaster has a height restriction of
“44 inches or taller”
(a) Let a represent a person’s height in inches.
Express the restriction by using mathematical notation.
(b) Suppose that nay rider whose height is within half an inch less than the height restriction is also permitted on the roller coaster. Express this modification by using mathematical notation.
(c) Photograph 2 was taken by Ron Lancaster at the box office of Eng Wah Cinemas in Singapore. Why do you think the cinema operators are concerned about the height of children who show up to see a movie? Is their concern similar to the concerns of the roller coaster operators?
(d) Is the conversion from nonmetric to metric units displayed on the sign in photograph 2 correct?
2. Photograph 1 shows the train engine and one car on the inclined track.
(Dis regard the second track in the center right of the photograph; no
questions will pertain to it.) The portion of the track shown here is just
long enough to hold the entire train, allowing all riders to have a view of
the ground below just before the train makes a sudden drop.
Assuming that the train engine and the cars are all the same
length, estimate the number of care that make up the train.
“ Mathematical Lens” uses photographs as a springboard
for mathematical inquiry. The goal of this department is to
encourage readers to see patterns and relationships that they can
think about and extend in a mathematically playful way.
Edited by Ron Lancaster
Ron 2718@nas.net
University of Toronto
Toronto, Ontario MSS 1A1 Canada
Brigitte Bentele
Brigitte. Bentele @ trinityschoolnyc.org
Trinity School
New York, NY 10024
Fig. 1 Constructing a triangle after importing the photograph into
GSP helps determine the slope of the track.
(b) Four people can sit front of the engine, and each car
holds six people. How many people can ride on the train at one time?
(c) According to the Web site www.articlealley.com/article_
917154_29.html, “Up to 2000 people an hour use the ride.” Do you
Think that more than one train is available for riders to use?
(d) According to the same Web site, “Bumper to bumper, the Expedition Everest train is over
20 meters long, while the track length is over 1,341 meters long.”
(i) How long is each car?
(ii) What percentage of the track appears in photograph 1 ?
3. Expedition Everest has a steep incline at the beginning of ride.
(a) Import Photograph 1 into the Geometer’s Sketchpad (GPS),use a ruler to measure the measure the sides of the triangle (see fig.1), and then calculate the slope of the incline.
(b) Photograph 1 was taken while the photographer was looking up at an angle. How does the real slops of the incline compare with your result from 3(a)?
(c) Express the slope of the incline determined in 3(a) in both systems described in figure 2.