Giving the Meaning of ExpressionI. Learning Objectives Cognitive: Define expressions. Translate word phrases to numerical expressions
|
WORD PHRASES | NUMERICAL EXPRESSIONS |
(Four times ten) divided by five Twelve diminished by two (Six times three) added to seven Eight added to the product of five and three Twenty-five added to two Three times twenty -five less twenty Thirty-six divided by six; 36 has how many 6 (Thirty-nine added to three) divided by seven |
(4 x 10) 5
12 — 2
7 + (6 x 3) 8 + (3 x 5) 25 + 2 (3x 25) — 20 36 + 6 (39 + 3) = 7 |
b. Activity 2 -."Create Your Own" (By Pairs)
3) Check answers.
2. Practice Exercises
5) your age plus your seatmate's age
3. Generalization
What is an expression? How do you translate word phrases into an expression?
C. Application
IV. Evaluation
Direction: Which expression is correct? Choose between A or B.
1. The sum of eleven and nineteen. A. 11 x 19 B. 11+192. Eight decreased by five. A. 8-5 B. 8x5
3. Twelve plus thirty-six. A. 12+36 B. 12x36
4. Five less than seven. A. 5x7 B.7-5
5. Four times the sum of two and five. A. 4x(2+5) B. 4x(5-2)
Direction: Write the expression for the following.
1. Seventy-five decreased by five2. Fourteen divided by the sum of three and four
3. Triple the sum of eleven and six
4. One more than the product of six and eight
5. Twenty plus five less than eighty
Direction: Write an expression for each problem/situation.
1. Helen is thirteen years old. Helen's father is four years more than twice her age.2. Edna is 155 cm. tall. Lilia's height is ten cm. less then twice Edna's height.
3. Roman weighs 25 kg. His father weighs five kg. less than three times Roman's weight.
4. Francis is ten years old. Ben is twice as old as Francis.
5. Aning is five years old. I am six years more than thrice her age.
V. Assignment
Give the Meaning of Equation, Exponent and Base.
I. Learning Objectives
A. Cognitive: 1. Give the meaning of equation, exponent and base
2. Evaluate an expression involving exponents
B. Psychomotor: Write simple equations
C. Affective: 1. Appreciate beauty
2. Be clean and orderly
II. Learning Content
Reference: Math Textbook, BEC PELC A.1.1.1
Materials: chart, roulette
Value: 1. Appreciation for beauty 2. Be clean and orderly
Ill. Learning Experiences
A. Preparatory Activities
1. Review/Drill
2) Teacher gives an operation, say "addition."
3) Each member of the group simultaneously goes to the board and writes a term or phrase that refers to the given operation
Ex. more than, increased by, plus, added to
4) Within 2 minutes, each group has to write as many terms or phrases as they can. The teacher checks and counts the correct answer.
5) Repeat the same process with subtraction, multiplication and division.
6) The group with the most number of correct answers wins.
2. Motivation
b) The Philippines is in the Southeast Asia.
c) Every Filipino celebrates Christmas in the 12th month of the year.
B. Developmental Activities
1. Presentation
Activity 1
b) What is the shape of their table?
c) Where will she use the tablecloth?
d) Where is the table placed?
e) Why does Rhoda need to sew a tablecloth for their table?
f) If you were Rhoda, will you also have to sew a table cloth? Why?
b) What number sentence best fits to the problem? 9 x 9 = N
c) What makes your sentence true? What sign is used to show that your sentence is true?
d) If the sentence is true, what is its other name? (equation) Are the two quantities equal?
e) Write the equation about the problem. (9 x 9 = 81)
f) Rename the 81 as a product of 9 x 9.
What does exponent mean? base?
h) Write the exponential notation about the problem.
Activity 2 - Use of Proving
16 [ =,≠ ] 9
16 ≠ 9
What do you call this number sentence having two equal quantities?
Rename 9 as a product of 3 x 3.
What do you call 3 in 32? 2 in 32?
What is the number multiplied by itself twice? What number tells you that 3 is multiplied by itself twice?
What is exponent? base?
Activity 3- Use of Illustration
Rename 25 as a product of 5 x 5.
What is meant by 52? What is 5 in 52?
What is 2 in 52? What is exponent? base?
2. Fixing Skills
a) 18 - ___ = 5 + 6 d) 96 - ___ = ___ + 24
___ = 11 72 = 72
b) ___2 = 10x ___ e) 1+ ___ + ___ = ___ x 1
100 = 100 6 = 6
c) ___ 3 = 8 --
64 = 64
3. Generalization
C. Application
1) Mang Sixto plans to have a rectangular terrace 3 m by 4 m. After a while, he changes his plan. He thinks of having the maximum perimeter possible.
2) A germ splits into 2 at a certain size with such situation the germ will have 6 splittings.
3) An order from a certain food chain for value meal costs P60 with P3 VAT and a delivery fee of P10 each. The five friends made an order.
IV. Evaluation
2) ___3 = 3 x 9 5) 91 ÷ ___ = 6 + ___
27 =___ 13 = 13
3)9 x ___ =___ x 27
54 = 54
2. If A is 4, then 12 = A = 3 + 2
3. If Z is 5, then 20 - 2Z = 10 - Z
4. If L is 6, then 2L - 4 = 8
2) The least perimeter possible for a rectangular garden having an area of 24
m2.
3) The cost of a girl's underwear when a dozen of it is P180.
4) A meter of cloth is P75 and another cloth costs 6 metres at P468. Which is a
good buy?
V Homework
___2 = 36 ÷ ___
___ x 6 = 294 ÷ ___
Giving the Meaning of Exponent and Base, Evaluating Expressions Involving Exponents
I. Learning Objectives
Cognitive: 1. Give the meaning of exponent and base
2. Evaluate an expression involving exponents
Psychomotor: Write numbers in exponent form
Affective: Being aware of some dreaded diseases
II. Learning Content
Reference: BEC PELC- A.1.1.1.2, A.1.1.1.3
Materials: Flashcards, charts, activity cards
Value: Awareness of dreaded diseases
III. Learning Experiences
A. Preparatory Activities
Example:2+2=2x2=4
Expected Answers: 3 + 1.5 = 3 x 1.5 = 4.5
11 + 1.1 = 11 x1.1 = 12.1
B. Developmental Activities
1. Presentation
DAY NUMBER | NUMBER OF CANCER CELLS |
1 2 3 4 5 6 7 8 9 10 |
2 (2) (2) = 4 (4) (2) = 8 (8) (2) = 16 (16) (2) = 32 (32) (2) = 64 (64) (2) = 128 (128) (2) = 256 (256) (2) = 512 (512) (2) = 1024 |
- How is this obtained?
(The number of cancer cells in a given day is obtained by multiplying the number of cancer cells present on the preceding day by 2 since the cancer cells double daily.)
- If we try to rewrite this product in terms of the number of cancer cells . present on the first day, we will have the following table.
DAY NUMBER | EXPRESSION IN TERMS OF THE NUMBER OF CELLS | NUMBER OF CELLS PRESENT |
1
2
3 4 5 6 7 8 9 10 |
2 2 (2) 2 (2) (2) 2 (2) (2) (2) 2 (2) (2) (2) (2) 2 (2) (2) (2) (2) (2) 2 (2) (2) (2) (2) (2) (2) 2 (2) (2) (2) (2) (2) (2) (2) 2 (2) (2) (2) (2) (2) (2) (2) (2) 2 (2) (2) (2) (2) (2) (2) (2) (2) (2) |
2 4 8 16 32 64 128 256 512 1024 |
- Let us focus our attention on the expression that describes the
number of cancer cells in a given day in terms of cancer cells present
on the first day. This is seen in the second column of table 2.
- What can you say about the writing of the expression? Why?
(It becomes tedious because we write the number repeatedly.)
- It is for this reason that in 1637, Rene Descartes, a French
mathematician, introduced a system of writing numbers indicating
repeated multiplication.
What can you say about Rene Descartes? Do you want to be like him someday? Why?
2. Fixing Skills
1.16 = 4 x 4 = ____ = ____
16 = 2 x 2 x 2 x 2 = ____ = ____
2. 81 = 9 x 9 = ____ = ____
81 = 3 x 3 x 3 x 3 = ____ = ____
3.100 = 10 x 10 = ____ = ____
100 = 2 x 5 x 2 x 5 = ____ = ____
4.125 = 5 x 5 x 5 = ____ = ____
5.144 = 12 x 12 = ____ = ____
144 = 3 x 4 x 3 x 4 = ____ = ____
3. Generalization
The base is the number used as the factor.
IV. Evaluation
A. Formative Test
Directions: Complete the following sentences.1. In 53, __________ is the base and __________ is the exponent.
2. 62 is the exponent form of 6 x ____.
3. 144 is the _______ power of 12.
4. 24 means 2 multiplied by itself ________ times.
5. 74 means _________ is multiplied by itself four times.
B. Give the value of the following.
1. 632. 45
3. 27
4. 92
5. 74
V. Assignment
2.16= ____ x ____ = ____2
3. 8 = 2 x 2 x 2 = 2-
4.102 = 10 x 10 = ____
5.103 = ____ x ____ x ____ = _____
Complete the pattern. 31 32 33 34 35 36 37 38
Evaluating an Expression with Two Different Operations with Exponents and Parenthesis/Grouping Symbols
I. Learning Objectives
Cognitive: Evaluate an expression with two different operations with exponents and parenthesis/grouping symbols
Psychomotor: Write the solution in evaluating the numerical expression
Affective: Be clean and orderly
II. Learning Content
Ill. Learning Experiences
A. Preparatory Activities
1. Mental Computation: Drill on Giving an Expression
a. Activity I
Mechanics:
2) The leader having drawn number 1 opens the problem and reads aloud.
3) Each group decides within 60 seconds.
4) One member of each group simultaneously goes to the board and writes the numerical expression.
5) The teacher together with the class check the answer.
6) The other leaders follow one at a time according to the number drawn.
7) The group having the highest number of correct answer wins.
b. Activity 2— Game on Writing the Word Expression
2. Review
a. Activity 1
Mechanics:
b. Activity 2
Mechanics:
3. Motivation
B. Developmental Activities
1. Presentation
a. Activity 1 — Use of Counters
2 x 9 + 8
18 + 8
26
b. Activity 2 - Use of Illustration Sample:
(Make your illustration here.)
1) Have the pairs of pupils answer the following questions?
48 + 5
53
c. Activity 3— Use of Problems in the Homework
a. (2 x 52) + 3 d. (82 ÷ 4) + 23
b. (8 ÷ 2) + 23 e. 92 ÷ (32 + 18)
c. (18 + 6) ÷ 23
b) What operations must be used? Which operation comes first? last? Which operation should be used first? 'Why? Next? ' Why? Last? Why?
(2 x 25) ± 3 4 + 8 24 ÷ 8
50 + 3 13 3
53
d. (82-4)+23 e. 92 ÷ 32 + 18)
(64 ÷ 4) + 8 81 ÷ (9 + 18)
16 + 8 81 ÷ 27
24 3
2. Practice Exercises/Fixing Skits
Evaluate the expressions.
c. (16 - 7)2 - 23
d. (8 + 82) ÷ 24
e. (36 - 9) + 52
3. Generalization
C. Application
a. Write an expression about the problem. Then evaluate the expression.
100
500
IV. Evaluation
Evaluate the following expressions.
2) ( 2+ 32) x 5 7) ( 82 + 62 ) - 43
3) ( 25 - 15 )3 + 42 8) ( 32 - 23 ) + 8
4) 8 + (5 - 3)5 9) ( 7 - 5 )2 x 52
5) (8 x 33) - 42 10) ( 3 + 4 )2 + 51
V. Homework
1. Evaluate the following expressions.
b. 1002 - (32 x 5)2
c. (42 ÷ 7) x 23
d. (3 + 4)3 + 6
e. (7 - 3)3 x 52
2. Write a problem. Make an expression about it. Then evaluate.
Evaluating an Expression with Two Different Operations Without Exponents and Parenthesis/Grouping Symbols
1. Learning Objectives
Cognitive: Evaluate an expression with two different operations without exponents and parenthesis/grouping symbols
Psychomotor: Write a solution in evaluating an expression
Affective: 1. Be helpful in the family 2. Be honest
II. Learning Content
III. Learning Experiences
A. Preparatory Activities
1. Mental Computation: Drill on Giving the Expression of the Situation
a. Activity I — Game on Numerical Expression
b. Activity 2— Game on Naming the Word Expression Mechanics:
2. Review
a. Activity 1 — Naming the Baby
b. Activity 2 — Stating the Equation
Example: For the next 7 years Minerva turns 27 years old. How old is she now?
Possible Answers: N = 27 — 7
b) The teacher flashes the situation.
c) Each group thinks aloud and decides within 60 seconds for their answers.
d) The teacher checks the answer.
e) The group with the most number of correct answers wins.
3. Motivation
B. Developmental Activities
1. Presentation
a. Activity I — Use of Role Play in a Sari-Sari Store
1) Ask the following questions:
b) Who delivers dozens of eggs?
c) How many dozens of eggs are delivered to them ?
d) If you were Jethro:
• will you keep the change given by the delivery man? Why?
2) Have each pair of pupils act it out using play money and ask them to answer the following:
b) What are the operations to be used?
3) Lead each 'pair of pupils to think of an expression related to the problem.
4) Let them evaluate the expression they have formulated?
P160 + P840
5) Require them to analyze which operation they use before arriving at the exact change.
b. Activity 2— Use of Counters in Evaluating Expression Sample:
1) Ask the following questions:
b) How many items does the test have?
c) How many points does each item have?
d) If you were Dangdang will you also study hard? Why? Can you help your family when you study hard? Why?
2) Have each pair of pupils use counters to visualize the problem. Let them answer the following questions.
b) What are the processes to be used?
3) Guide each pair of pupils think of an expression in relation to the problem.
4) Let them think: Why must Dangdang be wrong? Ask them to evaluate the expression.
10 - 8
2
5) Oblige each pair of pupils analyze which operation they use before arriving at the missed points.