M A T H E M A T I C S

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Modified In-School Off-School Approach Modules (MISOSA)

Distance Education for Elementary Schools

SELF-INSTRUCTIONAL MATERIALS

MULTIPLICATION OF 5- OR MORE DIGIT FACTORS BY MULTIPLES OF 10, 100

AND 1 000

Department of Education

BUREAU OF ELEMENTARY EDUCATION 2nd Floor Bonifacio Building DepEd Complex, Meralco Avenue Pasig City

Revised 2010 by the Learning Resource Management and Development System (LRMDS),

DepEd - Division of Negros Occidental under the Strengthening the Implementation of Basic Education

in Selected Provinces in the Visayas (STRIVE).

This edition has been revised with permission for online distribution through the Learning Resource Management Development System (LRMDS) Portal (http://lrmds.deped.gov.ph/) under Project STRIVE for BESRA, a project supported by AusAID.

Section 9 of Presidential Decree No. 49 provides: “No copyright shall subsist in any work of the Government of the Republic of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for exploitation of such work for profit.” This material was originally produced by the Bureau of Elementary Education of the Department of Education, Republic of the Philippines.

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MULTIPLICATION OF 5-OR MORE DIGIT FACTORS BY MULTIPLES OF 10, 100 AND 1 000

Objectives: Multiply 5-or more digit factors by multiples of 10, 100 and 1 000.

Do you remember how to multiply a number by 10, 100 and 1 000? Try to the following:

1. 4 x 10 = 6. 4 x 100 = 11. 25 x 1 000 2. 6 x 10 = 7. 5 x 100 = 12. 30 x 1 000 3. 7 x 10 = 8. 6 x 100 = 13. 11 x 1 000 4. 8 x 10 = 9. 7 x 100 = 14. 45 x 1 000 5. 9 x 10 = 10. 8 x 100 = 15. 40 x 1 000

Check your answer using the key to correction. If your score is 13 or 15,

you may now proceed to this module. If you get 12 correct answers or below, review first the past lessons.

1. Do you know what a typhoon is? 2. What do you think typhoon will bring us? 3. Can you go to school if the typhoon is signal number 2? 4. Is it safe for you to go out and play during typhoon? 5. What do you feel when there is typhoon? 6. Have you tried giving something to people who are victims of typhoon? 7. What do you feel if you have given something to people who are

victims of typhoon?

Review

Study and Learn

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Read the problem. Analyze the problem.

1. What hit Pangasinan last June? Typhoon

2. What did the president promise each municipality hit by typhoon?

The president promise to give each municipality the amount of 340 252.

3. How many municipalities were hit by typhoon?

There were 10 municipalities.

4. What is asked for?

How much amount will be given to Pangasinan.

5. What are given in the problem?

340 252 - amount to be given to each municipality 10 - number of municipality hit by typhoon

6. What operations will help you solve the problem?

Multiplication

7. What is the number sentence

340 252 x 10 = N or 340 252 x 10

Some parts of Pangasinan were badly hit by typhoon last October. The president promised to give each municipality who were victims of typhoon an amount of 340 252. If there were 10 municipalities and victims of typhoon, how much amount will be given to Pangasinan?

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You can use a short cut to multiply any number by 10 or a multiple of 10 340 252 x 10 3402520 - write 0 in the ones place Then multiply by the tens digit Try to multiply multiples of 100

622 437 Write 0 in ones place and tens places. x 100 Then multiply by the hundred digits

62 243 700

How about in multiplying any number by a multiple of 1 000? Try this: 5 622 437 Write 0s in the ones tens and hundreds places. 1 000 Then multiply by the thousand digit

5622437000

Try to find the pattern for the following exercises.

A. B. 52 163 x 4 = 208 652 421 846 x 3 = 65 538 52 163 x 40 = 421 846 x 30 = 52 163 x 400 = 421 846 x 300 = 52 163 x 4 000 = 421 846 x 3 000 =

What pattern did you observe? How do you multiply numbers by multiples of 10? 100? 1 000?

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Are you now ready to have exercises? Do it in your notebook.

A. Answer the following. Bring down the zeros before multiplying.

a) 31 772 b) 24 634 c) 753 321 d) 821 245 e) 9 638 452 x 10 x 30 x 200 x 500 x 1 000

B. Solve for n.

1) 31 142 x 500 = n 4) 822 134 x 1 000 = n 2) 72 413 x 900 = n 5) 7 518 321 x 4 000 = n 3) 62 214 x 2 000 = n 6) 40 056 times 40 = n, find n 7) What is n in 8 402 x 200 = n? 8) What is 23 204 times 252 equals n?

C. Complete the table. Write them in your notebook

X 400 2 000

1) 34 345 2) 123 632 3) 925 867 4) 532 324 5) 1 134 262

8)

Try These

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Are you now ready to test how for you have learn the lessons? A. Answer the following. Do it in your notebook.

1) 32 186 2) 23 272 3) 521 832 4) 1 833 143 5) 4 718 321 x 10 x 100 x 1 000 x 500 x 7 000 B. Solve for n.

1) 42 133 x 400 = n 4) 622 235 x 1 000 = n 2) 42 314 x 900 = n 5) 1 734 423 x 400 = n 3) 364 213 x 2 000 = n

Check your answer with the answer key. If you get…. 8-10 - Excellent! You may now proceed to the next lesson. 7-5 - You need to review the processes you missed. 0-4 - You need to repeat the whole process.

Ask your teacher or elder to help you.

How do we multiply numbers by multiples of 10? 100? 1 000?

- Multiply the non-zero digits first, then annex to the product as

many zeros as there are in the factors.

Wrap Up

On Your Own