This Instructional Activity is part of the the Lesson 10, Unit 2, Grade 5. This task is very challenging, and if left to their own devices, students may take much more time than would allow for Anchor Task #2 and the Problem Set. However, since solving the task would result in lots of practice of multi-digit multiplication problems with various-sized factors, it is at the teachers discretion to allow students to spend the whole lesson doing so.