Lesson 79

Measuring Area using Appropriate Units

BY SIR. REI MARASIGAN

ALAMINOS DIST.

LAGUNA DIV

Drill

Look at the following shapes. Name the shapes and tell the number of its sides.

Review

Count and tell the number of squares in the figure.

16 SQUARES

5 SQUARES

9 SQUARES

Motivation

If you are to buy a plastic cover for your books, what is the

appropriate unit of area measure to be used? Why?

Presenting the Lesson

Post the problem on the board.

Diana and Jean bought notebooks at the mall. They also bought plastic cover for their notebooks. What is the area of the

top of the notebook to be covered?

What is the appropriate unit

of area measure to be used? Why?

• What do we need to find in the problem?

(area of the notebook and appropriate unit in measuring area)

• What measuring tool can we use to get the length of this notebook?

(ruler, tape measure)

• What standard unit of measure can we use to get the length of this notebook?

(centimeter or cm)

Performing the Activity

a. Using square centimeter (sq. cm)

Divide the class into groups of 4s.

Provide each group with a 1 cm by

1 cm grid paper approximately the size of their notebook. e.g.

1 cm

1 cm

• What is the area of this paper?

(300 square units)

Let pupils count the small squares.

Measure the length of one small square.

• What is the length of the side of one small square?

(1 cm)

What is the area of one small square?

​

(1 square centimeter or 1 cm2)

What standard unit of area measure did we use to find the area ?

(square centimeter or sq. cm)

Processing the Activity

How did you find the activity?

Is it easy or difficult?

If a different person

will measure the area of a book and floor of the room, do you think

he/she will get the same answer as yours?

What instrument or measuring tool did we use in the activities?

(ruler, meter stick, carpenter’s tape measure)

What did we measure?

(area of the notebook, room)

What will help you decide the appropriate unit to use in measuring area?

(When the area to be measured is small, for example, book, pad paper, etc., the appropriate unit is square centimeter. If the area to be measured is bigger, like the garden, the floor of a room, etc., then the appropriate unit is the square meter.)

Reinforcing the Concept

Piliin ang pinakaangkop na yunit na dapat gamitin sa

sumusunod. Isulat sa patlang ang metrong kuwadrado

(sq.m) o sentimetrong kuwadrado (sq.cm)

1) Silid = ________________

2) hardin= ________________

3) lagayan ng sapatos= ________________

4) tile ng sahig = ________________

5) manila paper = ________________

6) sahig ng stage = ________________

7) Aklat = ________________

8) cartolina________________

9) ibabaw ng mesa ng guro= ____

Summarizing the Lesson

When do we use square centimeter

(sq. cm)? square meter (sq. m)

When measuring smaller area, like a book, greeting card, etc., we use the square centimeter

(sq. cm).

When measuring bigger area, like the garden, floor of a room, etc., use the square meter

(sq. m).

Applying to New and Other Situations

Ibigay ang angkop na yunit sa sumusunod na sitwasyon:

1)Nais ni Brian na sukatin ang area ng kanilang

mesang kainan, ano ang angkop na yunit na

dapat niyang gamitin?

2)Anong angkop na yunit ang gagamitin ni Maria

sa pagsukat ng area ng plaza?

3) Ang angkop na yunit para masukat ang area ng

parihabang lawa ay __________.

4) Ang yunit na angkop sa area ng panyo ay

___________.

Evaluation

Gamitin ang panukat. Hanapin ang area ng sumusunod na gamit at isulat ang angkop na yunit.

1)Plot ng hardin sa likod ng paaralan

2)Sahig ng banyo

3)Silid-tanggapan

4)Mahabang envelop

5)Christmas card

Home Activity

Look around your house. Give 5 things or figures which can be

measured using square centimeters and another 5 things or places which

can be measured using square meters.