- http://library.thinkquest.org/04oct/00398/ThinkquestHome_files/Thinkquest/Lia%20Web%20Page.htm
- “Jessica is designing a model of Mt. Rushmore. Mt. Rushmore is 500 feet high and 400 feet wide. Based on
a scale of 1[U+0080][U+009D]=25 feet, what are the dimensions of Jessica’s model?” - “When you are sure that you have the correct measurement, use grid paper and draw a diagram of Jessica’s
model. Be sure to draw your diagram to scale.” - Solution:
- 1[U+0080][U+009D]=25 feet
- 500 feet high= 20 [U+0080][U+009D]high
- 400 feet wide= 16 [U+0080][U+009D]wide
- The students can draw this free hand using a ruler and large sheets of paper, or they can use grid paper to
create another scale using the units on grid paper and then draw a diagram there. - Allow time for the student to share their work when finished.
III.MeetingObjectives
- Students will use scale models or scale drawings.
- Students will apply what they have learned about scale models and drawing when problem solving.
IV.NotesonAssessment
- Is student work accurate?
- Does the diagram accurately represent the measurement of Mt. Rushmore?
- Have the students used the scale and proportion to come up with the correct measurements?
- Provide students with coaching and feedback.
Circumference and Arc Length
I.SectionObjectives
- Understand the basic idea of a limit.
- Calculate the circumference of a circle.
- Calculate the length of an arc of a circle.
II.ProblemSolvingActivity-TheCul-de-sacQuestion
- Here is the problem.
- Figure 10.04.01
- “Janine lives on a cul-de-sac. The diameter of the cul- de- sac is twenty- four feet. There is one road into
the cul- de- sac and the measure of that arc is 60◦. Janine would like to plant flowers along the edge of the
cul-de-sac, but she does not need to plant them where the road is. How many feet can Janine plant?” - Solution:
- Students will need to do several steps to figure this one out.
- First, find the circumference.
- The circumference is 75.36 feet.
- Next figure out the arc length.
- The measure of the arc is 60◦.
- The arc length is 6.28 feet.
- Now subtract the arc length from the circumference.
- 36 − 6. 28 = 69. 08
5.10. Perimeter and Area