# Day 139 – Two Interesting Problems

Math 8Who Gets There Faster, Jim or Stan?

Today I worked on giving most of the instructions/prompts verbally. I thought it would be prudent to write down the numbers required though.  Maybe I should have tried it without the writing.

And a nice solution below…

While several groups clued in that distance/speed is time, lots of groups used equivalent ratios for their solution, which I was fine with.  The reasoning would be something like “Jim goes 9km in 2hrs, 13.5 km in 3hrs, and over 11km in 2.5 hours…”

The next problem was simply stated: I have a rectangular prism with side lengths 8, 9 and 12.  What is the furthest distance from one point to another?  One solution is shown below.  Once students were able to picture the vector they needed, many were able to find the correct answer. I liked this problem because it had a low floor – all groups were able to find some diagonals using the Pythagorean Theorem.

I was very proud of this lesson, both for what I had planned and on what students were doing. Virtually all the students were engaged and accountable. Even border kids who typically sit back a bit were interested in working on possible solutions.