2. About Crossing the River
Crossing the river is an activity based on algebra and
patterns.
This activity can really help you understand how to
ïŹgure out patterns in algebra and to use logic to ïŹgure
it out.
3. Introduction
First, we got split up into small groups of 3 (one group
of 4). I was in a group with Alpha-Adventurer 6 and 18.
In those groups, we had to ïŹgure out problems that
our teacher gave us.
Next, our teacher read the instructions to us, here are
the instructions:
On the weekend, friends of mine went camping. They were camping on a
small island in the middle of the lake. There were eight adults and two
children in all.
When they went to cross the lake and return home their boat was
missing. They searched and searched but all they could ïŹnd was an
old canoe. It wasnât as big as the boat and they were worried it
wouldnât carry them all. So, they tested it and found the boat could
carry either:
âą
One adult
âą
One or two children
At ïŹrst they thought some of them would be stranded forever, but ïŹnally,
they ïŹgured out how to get them all safely across the lake.
4. The Process
Then, my group and I did some planning and thinking
on how can the 8 adults and 2 children go to their
home island, and ïŹnally, we came up with a solution.
Our solution was the 2 children go across the river
back to the home island, then a child goes back to the
camping island, the child gets off the boat and an adult
goes back to the home island. After the adult goes
back to the home island, the child who was left there
goes on and gets the child from the camping island.
For this process (8 adults and 2 children), they go back
and forth 33 times.
5. The next step
After that, we had another set of instructions:
What if one of the adults was sick and didnât end up
going camping? How would that change the number of
crossing? (that will be 7 adults and 2 children).
Next, my group ïŹgured it out again and we got the
number 29.
6. The last step
After all of that, we had to make your own number of
adults and had to ïŹnd the function of the problem.
My group did a few and found out the function is x4
+1, that is multiply by four, and add one.
Here are examples:
5 adults = 21 times
3 adults = 13 times
100 adults = 401 times
7. Conclusion
Overall, this was a great activity for algebra and to
ïŹgure out patterns using your brain (logic).
I would really want to try this type of activity again!
Hope you enjoyed this presentation!