
Concept explainers
The Ferris Wheel In 1893, George Ferris engineered the Ferris wheel. It was 250 feet in diameter. If a Ferris wheel makes 1 revolution every 40 seconds, then the function
represents the height , in feet, of a seat on the wheel as a function of time , where is measured in seconds. The ride begins when .
a. During the first 40 seconds of the ride, at what time is an individual on the Ferris wheel exactly 125 feet above the ground?
b. During the first 80 seconds of the ride, at what time is an individual on the Ferris wheel exactly 250 feet above the ground?
c. During the first 40 seconds of the ride, over what interval of time is an individual on the Ferris wheel more than 125 feet above the ground?

To find:
a. During the first 40 seconds of the ride, at what time is an individual on the Ferris wheel exactly 125 feet above the ground?
Answer to Problem 104AYU
a.
Explanation of Solution
Given:
In 1893, George Ferris engineered the Ferris wheel. It was 250 feet in diameter. If a Ferris wheel makes 1 revolution every 40 seconds, then the function.
represents the height , in feet, of a seat on the wheel as a function of time , where is measured in seconds. The ride begins when .
Calculation:
a. During the first 40 seconds of the ride, at what time is an individual on the Ferris wheel exactly 125 feet above the ground?
When ,
When , , So they are 125 feet about the ground at 10 and 30 seconds.

To find:
b. During the first 80 seconds of the ride, at what time is an individual on the Ferris wheel exactly 250 feet above the ground?
Answer to Problem 104AYU
b.
Explanation of Solution
Given:
In 1893, George Ferris engineered the Ferris wheel. It was 250 feet in diameter. If a Ferris wheel makes 1 revolution every 40 seconds, then the function.
represents the height , in feet, of a seat on the wheel as a function of time , where is measured in seconds. The ride begins when .
Calculation:
b. During the first 80 seconds of the ride, at what time is an individual on the Ferris wheel exactly 250 feet above the ground?
So they are 250 feet about the ground at seconds.

To find:
c. During the first 40 seconds of the ride, over what interval of time is an individual on the Ferris wheel more than 125 feet above the ground?
Answer to Problem 104AYU
c.
Explanation of Solution
Given:
In 1893, George Ferris engineered the Ferris wheel. It was 250 feet in diameter. If a Ferris wheel makes 1 revolution every 40 seconds, then the function.
represents the height , in feet, of a seat on the wheel as a function of time , where is measured in seconds. The ride begins when .
Calculation:
c. During the first 40 seconds of the ride, over what interval of time is an individual on the Ferris wheel more than 125 feet above the ground?
When ,
When , , Ferris wheel more than 125 feet above the ground is between 10 and 30 seconds.
Chapter 7 Solutions
Precalculus
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