standard_description: Give an informal argument for the formulas for the circumference of a circle, area of a circle, volume of a cylinder, pyramid, and cone. Use dissection arguments, Cavalieri’s principle, and informal limit arguments.
problem_activity: Problem 1
Jenny buys 2 feet of string. If this is one-third the amount she needs to make a bracelet, how many feet will she need?
a.   Draw a diagram to represent the problem.
b.   Write an expression to represent the problem.
c.   Find how many feet of string Jenny needs.
Problem 2
a.   Match each division expression (cut out from
Template: Fraction Division Sort
) with a situation (cut out from
Template: Fraction Division Sort
). Some expressions do not have a matching situation.
b.   Answer each question. Be prepared to share your reasoning.
Problem 3
a.   Write a story context that can be solved using the expression
$${2\div{1\over4}}$$
.
b.   Write a story context that can be solved using the expression
$${{1\over3}\div4}$$
.


aligns: no