to Math Club

1
WELCOME
to Math Club
2
What is Math Club?

• Math Club is an organization for
• People that love math
• People that love mental mathematical tricks
• People that love to solve problems
• People that love to compete
• People that love number sense
• People wanting to participate in KASC

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What is Number Sense?

• It is more than a contest or a study of
  arithmetic. There are many practical
  applications of number sense in the everyday
  world. For example, many people are required to
  make decisions involving money each day money to
  pay for groceries, money to pay the babysitter,
  etc. Each time a person must make mental
  calculations in order to make a decision, he is
  using his number sense.

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• The development of number sense of the human race
  began at a long time agodistinguishing between
  few and many, comparing sizes of families, herds,
  etc. We are introduced to numbers at an early
  age and their use is unending throughout our
  lifetime. We are constantly exposed to numbers.

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• With the invention and widespread use of
  calculating devices there has been a decline in
  our sense of numbers. While calculators, slide
  rules (???), and computers have many uses and
  advantages, there are many times when they are
  used to perform calculations we could do mentally.

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• The ability to make mental calculations quickly
  and accurately is an artan art which may be
  developed by any person. How? By developing
  number sense. Number sense consists of
  recognizing the relationships that exist between
  numbers and using them in making calculations.

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• Each week, we will
• Practice previous tricks
• Learn and practice a new trick
• Discuss some high level math problems
• All of this will
• Prepare us for tournaments
• Help us in math class
• Give us a better sense of numbers and problem
  solving.

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Each week

• We will meet on Wednesdays at 815 (Listen to the
  announcements. If a faculty meeting is called,
  we will have to notify you by the announcement
  that we have had to cancel math club for that
  week.)
• We will meet in the computer lab (if the location
  should change, we will post a sign on the
  computer lab door).
• You will need your note cards from previous
  weeks.
• You will need to sign in with your name, your
  teachers name, and your grade.

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Some of us have done this before

• There are a few of you that have being doing
  number sense and math club for a long time. We
  really need you to continue to come. We need
  your help during math club to help people
  learning skills for the first time. We need your
  knowledge and skills to pass on to other students
  in math club.

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Try these mentally. Write the answers on the
paper provided.

• 1. 25 10 200
• 2. 300 80
• 3. 75 5 x 2
• 4. 300 50 20 100
• 5. 2000 200 50 6
• 6. 200 x 4 2 70
• 7. (1/2 of 60) x 5, double it
• 8. 900 3 3 4
• 9. (234 50) 2

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• 10. 1000 40 1000 50 1000 10
• 2 pencils cost a quarter, erasers
• 11. What is the cost of 6 pencils and an
  eraser?
• 12. If you bought 4 pencils and 2 erasers,
  how much change do you receive from 1.00?

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Answers

• 1. 235 8. 25
• 2. 220 9. 142
• 3. 140 10. 3100
• 4. 230 11. 0.80
• 5. 2156 12. 0.40
• 6. 330
• 7. 300