standard_description: Know the formulas for the area and circumference of a circle and use them to solve problems; give an informal derivation of the relationship between the circumference and area of a circle.
problem_activity: Rishi is trying to find the total number of clouds in the following array.
[IMG]
Rishi says "I know 3 × 9 = 27, so I can use that to help me solve."
a.   Mark the array above to show how Rishi is thinking about it.
b.   Use the fact that
$$3\times9=27$$
to find the total number of clouds in the array.


aligns: no