Content Next

OVERVIEW OF THE MODULAR WORKBOOK

In this modular workbook, you will understand the concept of the language of decimal numbers. This modular workbook, will help you to read, write, and name decimal numbers for a given models, standard, mixed and technical and science work form. It provides the knowledge about place value, with the aid of a place - value chart. It also provides information on how to compare and order decimal numbers and also how to round off decimal numbers. This module will provide you a more difficult work in mathematics. Exercises will help the learners evaluate themselves to understand decimal numbers.

Back Next

OBJECTIVES OF THE MODULAR WORKBOOK

After completing this modular workbook, you expected to:

1. Know the language of decimal numbers.2. Read, write, and name decimal numbers in

different forms.3. Read and write decimal numbers with the aids of place - value chart.4. Compare and order decimal numbers.5. Rounding off decimal numbers by following

its rule.

Back Next

Lesson 1 WHAT IS DECIMAL?

Lesson ObjectivesAfter accomplishing the lesson, the students are expected to:

1. Define decimals.2. Identify the terms in decimal numbers.3. Familiarize the language of decimal numbers.

Lesson ObjectivesAfter accomplishing the lesson, the students are expected to:

1. Define decimals.2. Identify the terms in decimal numbers.3. Familiarize the language of decimal numbers.

Content Next

One important feature of our number system is the decimal. It involved many computational operations. It is very useful in the measurement of very thin sheets and in the computation involving in exact amount.

But what is decimal? Look at the following examples:

Back Next

a. .3 = 3 .03 = 3 10 100

.003 = 3 .0003 = 3 1000 10000

b. .5 = 5 .05 = 5 10 100.005 = 5 .0005 = 5 1000 10000

Back Next

From the example given above, a “decimal” may be defined as a fraction whose denominator is in the power of 10.

Back Next

Numbers in the power of 10 are 10, 100, 1000, 1000, etc. The dot before a digit in a decimal is called “decimal point” which is an indicator that the number is a decimal. The place on the position occupied by a digit at the right of the decimal point is called a “decimal place”.

Back Exercises

I. Give the meaning and explain the use of the following.

1. What are

decimals?

1. What are

decimals?

2. What is decimal point?

2. What is decimal point?

3. What is decimal place?

3. What is decimal place?

4. Give some

examples of decimal numbers.

4. Give some

examples of decimal numbers.

Back Next

1. Decimals ____________________________________________________________________________________

2. Decimal Point ____________________________________________________________________________________

3. Decimal Place ____________________________________________________________________________________

4. Examples

____________________________________________________________________________________

Back Next

II. Change the decimal numbers to fractional form.

Example: 0.8 = 8 10

1. 0.9 =_______________2. 0.1 =_______________3. 0.04 =_______________4. 0.06 =_______________5. 0.09 =_______________6. 0.001 =_______________7. 0.009 =_______________8. 0.0071 =_______________9. 0.0009 =_______________10. 0.0003 =_______________

Back Next

11. 0.0004 =________________12. 0.0005 =________________13. 0.00008 =________________14. 0.00009 =________________15. 0.148 =________________16. 0.79 =________________17. 0.1459 =________________18. 0.6 =________________19. 0.01 =________________20. 0.051 =________________

Back Home

Lesson 2READING AND WRITING DECIMAL

NUMBERS

Lesson ObjectivesAfter accomplishing the lesson, you are expected to:

1. Read and write decimal numbers.2. Follow the rules in reading and writing decimal numbers.3. Use the place value chart in order to read and write decimal numbers.

Lesson ObjectivesAfter accomplishing the lesson, you are expected to:

1. Read and write decimal numbers.2. Follow the rules in reading and writing decimal numbers.3. Use the place value chart in order to read and write decimal numbers.

Content Next

How to read and write decimals or decimal numbers? A decimal is read and write according to the number of decimal place it has.

Here are the rules in reading and writing decimal numbers.

Back Next

RULE I. A decimal of one decimal place is to be read and to be written as tenth.

.4 is read as “4 tenths” and is to be written as “four tenths”; 4/10.2 is read as “2 tenths” and is to be written as “two tenths”. 2/10

Back Next

RULE II. A decimal of two decimal places is to be read and to be written as hundredth.

.35 is read as “35 hundredths” and is to be written as “thirty – five hundredths”; 35/100.43 is read as “43 hundredths” and is to be written as “forty – three hundredths”.43/100Back Next

RULE III. A decimal of three decimal places is to be read and written as thousandth.

.261 is read as “261 thousandths” and is to be written as “two hundred sixty – one thousandths”; 261/1000.578 is read as “578 thousandths” and is to be written as “five hundred seventy – eight thousandths”.578/1000

Back Next

RULE IV. A decimal of four decimal places is to be read and to be written as ten thousandth.

.4917 is read as “4917 ten thousandths” and is to be written as “four thousand, nine hundred seventeen ten thousandths”; 4917/10,000.5087 is read as “5087 ten thousandths” and is to be written as “five thousand eighty - seven ten thousandths”.5078/10,000

Back Next

A decimal is read and written like an integer with the name of the order of the right most digits added.

tenths

hundredths

thousandths

ten thousandths

hundred thousandths

Millionths

ten millionths

hundred millionths

billionths

ten billionths

hundred billionths

trillionths

0 . 4 3 5 7 8 9 6 1 2 5 3 4 Back Next

Note: the names of the order of the different

decimal places.

QuadrillionthsPentillionthsHexillionthsHeptillionthsOctillionthsNonillionthsDecillionths

UndecillionthsDodecillionthsTridecillionths

…

Back Next

Examples: 0.4 Read as four tenths.

0.43 Read as forty-three hundredths.

0.435Read as four hundred thirty-five thousandths.

0.4357 Read as four thousand, three hundred fifty-seven ten thousandths.

Back Next

0.43578 Read as forty-three thousand, five hundred seventy-eight hundred thousandths.

0.435789 Read as four hundred thirty-five thousand, seven hundred eighty nine millionths.

0.4357896 Read as four million, three hundred fifty-seven thousand, eight hundred ninety-six ten millionths.

Back Next

0.43578961 Read as forty three million, five hundred seventy-eight thousand, nine hundred sixty-one hundred millionths.

0.435789612Read as four hundred thirty-five million, seven hundred eighty nine thousand, six hundred twelve billionths.

0.4357896125 Read as four billion, three hundred fifty seven million, eight hundred ninety six thousand, one hundred twenty five ten billionths.

Back Next

0.43578961253 Read as forty-three billion, five hundred seventy eight million, nine hundred sixty-one thousand, two hundred fifty three hundred billionths.

0.435789612534 Read as four hundred thirty-five billion, seven hundred eighty-nine million, six hundred twelve thousand, five hundred thirty-four trillionths.

Back Exercises

I. Write each decimal numbers in words on the space provided.

1. 0.167213143__________________________________________________________________

2. 0.52541876_____________________________ ______________________________________3. 0.263411859____________________________

______________________________________4. 0.984562910____________________________ ______________________________________5. 0.439621512____________________________ _______________________________________

Back Next

II. Write the decimal number in standard form.

1. Nine tenths______________________________________________2. Four hundredths______________________________________________

3. Two thousand, two hundred and two hundred thousandths____________________________________________4. Four hundred seventy – six millionths________________________________________________

5. Forty thousand, one hundred forty – one millionths________________________________________________

Back Home