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CSA FALL GM #5
Count on Us!
11.08.2017
RECAPS
Movie Night
Thanks for coming to our Halloween movie night!
Makahiki
Games
Hope you all enjoyed playing games with us and HONU!
Don't forget to come to our yo-yo workshop if you want to learn more!
Coming Up
COMING UP
Crestmaking and Family Potluck
Come with your bigs and smallls to create a crest for your family!
11/12 from 1-3:30
Curry 333
Chinese Yo-Yo Workshop
Friday, 11/17
7-9 PM
Cabot
Come learn how to use the Chinese Yo-Yo!
Hotpot Buffet
Saturday 11/18
12 - 1:30 PM
Hot Pot Buffet
Join CSA and the brothers of Pi Delta Psi for a day of all-you-can-eat hot pot!
The Abacus
THE ABACUS
A Brief History
The abacus, or "suan pan," as it appears today was first chronicled in 1200.
It appeared on the long scroll Along the River During the Qingming Festival, from the Song Dynasty.
How to Use an Abacus
Addition:
Group smaller value beads into higher value beads
Examples
(+/-)
Subtraction:
Dissolve higher value beads into lower value beads
139+68=?
139+68=?
Step 1: 139
Step 3: Add 60 (Split into 50 + 10)
Step 2: Add 8 (Split into 5 + 3)
Move up a 10
Move down a 50
Move down a 5
Exchange two 5s for a 10
Exchange five 10s for a 50
Exchange two 50s for a 100
Add 3 more, exchanging five 1s for a 5 in the process
207
300-47=?
300-47=?
Step 1: 300
Step 4: Subtract 7
Step 5: Subtract 40
Step 2: Dissolve 100 into 50s and 10s
Step 3: Dissolve 10s into 5s and 1s
Take away a 5 and two 1s
Take away four 10s
Replace a 100 for a 50 and five 10s
Replace a 10 for a 5 and five 1s
253
Game 1
In groups of 5-6 people:
Person 1 starts with a #
Persons 2-6 have calculations based on previous person's #
Example: Person 1 = 25, Person 2 = +12, Person 3 = -7, ...
Feel free to help each other, it's a team effort!
ACTIVITES
Game 1: Numbers
Game 1: Numbers
Person 1: 1,057
Person 2: +56
Person 3: -130
Person 4: -311
Person 5: +601
Person 6: -258
Game 1 Final Answers:
1: 1,057
2: 1,113
3: 983
4: 672
5: 1,273
6: 1,215
Game 2: Be the Abacus
Game 2: Be the Abacus
To understand the abacus, you must be the abacus.
Arrange in columns of 7 as though you are a bead and try to assemble the numbers as quickly as possible as an entire group. Numbers and calculations on the next slide. Ready?
Go!
Round 1: 1156
Round 2: +312
Round 3: -233
Round 4: +608
Round 5: -481