Evaluating Expressions

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2005 USM Summer Math Institute Co-Sponsored by
Institutions of Higher Learning (IHL) U.S.
Department of Education (No Child Left Behind
Funding) The Center for Science and Mathematics
Education The Department of Mathematics College
of Science and Technology College of Education
and Psychology
Day Six
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2005 USM Summer Math InstituteYour Mathematics
Instructors, Staff and Partners

• Ms. Michelle Green, Co-Director and Co-Instructor
  for (SM)2I
• Stringer Attendance Center
• Eighth Grade Teacher
• Email mdwgreen_at_hotmail.com, Phone [phone]
• Dr. Myron Henry, Director and Co-Instructor for
  (SM)2I
• Department of Mathematics and the Center for
  Science and Mathematics Education
• Johnson Science Tower 314
• Email myron.henry_at_usm.edu, Phone [phone] or
  266-6516
• All Participants (thats you)

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(SM)2I
A week in review
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Summer 2005
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Annette Bingham, Shauna Hedgepeth, and Amy
Bullock Hey, we are having fun with this
spreadsheeting stuff!
Rita Ward, Thalita Hosey, Darius Thurmon, and
Willene Magee Darius must be on to some serious
mathematics!
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Karen Schumacher and John Fewell all right, if
you must have a picture, we guess its o.k. But
we want to get back to this exciting mathematics!
Cindi Pardew, Leigh Thacker, Michelle Green, and
Shauna Hedgepeth a serious study of
mathematics? Or maybe something isnt working.
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Dana Pittman and Felicia McCardle This power
point presentation will be dynamite!
Monica Cobbert and Sharon Shepeard Geometry and
technology, like sand and the beach!
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Day Six of (SM)2I
Day six. Pp presentations built by us. Let's
present!

• Finish Power Point Slides
• Power Point Presentations (15
  minutes per team)
• Calculator Activities
• Evaluating expressions
• Boolean Algebra
• Mean, median, mode

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Day Six of (SM)2I
Day Six
TI 84 Plus Silver Edition!
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Hi Oh Silver Away!
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(No Transcript)
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Evaluating Expressions

• Example Evaluate 2/3 x 100 when x
  16.5

Keystrokes 1 6 .5 x e (16.5 will be x
until you store a new value for x.)
( 2 / 3 ) x 10 0 e
advise your students to always put fractions in
parentheses!!!!

• Example Evaluate 5/(8x) when x 2.
• Is 5/8x the same expression? Evaluate and see if
  you obtain the same answer for x 2.
• Moral of story using ( ) makes it clear what
  you mean to others and your calculator!

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• Practice Evaluate the following expressions
• if x 4, m 5, and p -2
• xmp
• m2/px,
• m2p/x,
• 4y3z if y -2 and z 10
• -x - (-a b) if x 2, a -4, and b -6
• x - y( - a2 x ) if x -2, y 3, and a -
  4

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Suppose you want to evaluate a formula V ? r2
h if the radius of a right cylinder is 12.5
inches and the height is 18 inches. You would
store the values for r and h just like the above
example and then type the formula on the home
screen. Suppose you were comparing the volume of
two right cylinders and the other cylinder had a
radius of 18 inches and a height of 12.5 inches.
Simply store the new values for r and h, but in
stead of retyping the formula use the replay
feature e
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Boolean Algebra

• (True or False)

This activity will allow students to check their
work without getting the answer from the
calculator.   Example 47
102  The student wants to check her answer of
54  Assign the box an alphabetical letter such as
X.
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Keystrokes 54 x e x 47 m 1 e The
calculator will either show a 1 which means
TRUE ( their answer is correct) or a 0 which
means false ( their answer is incorrect ).  
Students can check any kind of problems that they
encounter using the Boolean method.  Try
these  1.    X - 47 229, X ______
 2.    ½ ¼ _____ (ALWAYS PUT
FRACTIONS IN PARENTHESIS)  3.    2.97 x 104
______  4.    34 _____
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Mean, Median and Mode
82 91 74 78 94 68 74 88 64 42 72 82 79 99 98 75 61
78 86 69  Enter this data in L1
S 1 To clear list arrow up and clear
enter  Enter data S gt and access the
option   1 var-stats e
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If your information is not in L1 you must tell
the calculator where it is.  Ex. S gt L1   Find
the Average and Median.   85 72 94 85 76 94 81 52
79 100  The calculator will put this in
ascending or descending order for you. S 2 or
S 3