Math Spies Taking Inventory: Multiplying Large Numbers

Have you visited Math Spies?  Here is where I post math problem-solving tasks for my students, and other teachers are welcome to use it.  (I am taking a break from posting this summer, but the archives are full of problems.)

The series Taking Inventory is about multiplying large numbers.  Here are the links to the seven problems:

 

Taking Inventory #1

Taking Inventory #2

Taking Inventory #3

Taking Inventory #4

Taking Inventory #5

Taking Inventory #6

Taking Inventory #7