Mental Math Multiply Two Numbers With Same Tens And Sum Of Ones Is Ten

Previous Requirement Lessons

Basic Number Operation Vocabulary 1

Number Place Value In Mathematics

General Condition:

• Two factor numbers has same tens in number place value.
• Two factor numbers has sum of ones are tens.

Learning Direction

• Student can find the product number more simplified.
• Student get more understand for mathematics concept with practice the following examples.

Method 1 Example

82 × 88 = ...

• Factor numbers in this example are 82 and 88.
• Multiplication sign is ( × ).
• Equal sign is ( = ).
• Product number in this example is ( ... ).

First Step

Split tens with ones for each factor numbers.

82 × 88 = ( 80 + 2 ) × ( 80 + 8 )

Second Step

Multiply ones digit factor (last number) with the other ones digit factor (last number). If the product number in this step only result in ones digit, add zero in the tens number place value.

82 × 88 = ... ( 2 × 8 )

82 × 88 = ... 16

Third Step

Multiply the tens digit factor with the other ten digits factor.

82 × 88 = ( 80 × 80 ) + 16

82 × 88 = 6400 + 16

Fourth Step

Multiply the tens digit with 10.

82 × 88 = 6400 + ( 80 × 10 ) + 16

Result Step

Adding all the result from the previous step with the result in the previous step

82 × 88 = 6400 + 800 + 16

82 × 88 = 7216

Method 2 Example

71 × 79 = ...

• Factor numbers in this example are 71 and 79.
• Multiplication sign is ( × ).
• Equal sign is ( = ).
• Product number in this example is ( ... ).

First Step

Split tens with ones for each factor numbers.

71 × 79 = ( 70 + 1 ) × ( 70 + 9 )

Second Step

Multiply ones digit factor (last number) with the other ones digit factor (last number). If the product number in this step only result in ones digit, add zero in the tens number place value.

71 × 79 = ... ( 1 × 9 )

71 × 79 = ... 9

71 × 79 = ... 09

Third Step

Add result split tens ( from first step ) with 10 number then multiply with result split tens.

71 × 79 = [ ( 70 + 10 ) × 70 ] 09

71 × 79 = [ 80 × 70 ] 09

71 × 79 = 5609

Method 3 Example

56 × 54 = ...

• Factor numbers in this example are 56 and 54.
• Multiplication sign is ( × ).
• Equal sign is ( = ).
• Product number in this example is ( ... ).

First Step

Multiply ones digit factor (last number) with the other ones digit factor (last number). If the product number in this step only result in ones digit, add zero in the tens number place value.

56 × 54 = ... ( 6 × 4 )

56 × 54 = ... 24

Second Step

• Identify the factor number has difference 1 between tens and ones. If there are same identifier between two numbers, choose the biggest one.
• Multiply the ones with ten.

56 × 54 = [ 50 × ( 6  × 10 ) ] + 24

56 × 54 = [ 50 × 60 ] + 24

Third Step

Multiply the tens number with the number from the result.

56 × 54 = [ 50 × 60 ] + 24

56 × 54 = 3000 + 24

56 × 54 = 3024

Bibliography

https://byjus.com/

https://www.ck12.org/

https://www.mathnasium.com/

https://www.splashlearn.com/

https://www.wikihow.com/

GBoard Simplified Chinese Terms

GBoard Languages And Layout Keyboard

Han4Zi4 : Pin1Yin1 : Zhu4Yin1 : English

按住並拖曳即可自訂 : Àn Zhù Bìng Tuō Yè Jí Kě Zì Dìng : Hold And Drag To Customise.

变更键盘 : Biàn Gēng Jiàn Pán : Change Keyboard.

表情待号 : Biǎo Qíng Dāi Hào : Emoji.

重设 : Chóng Shè : To reset.

重做 : Chóng Zuò : Redo.

打开 : Dǎ Kāi : Open.

单手 : Dān Shǒu : One Handed.

繁体字 : Fán Tǐ Zì : Traditional Chinese Character.

返回 : Fǎn Huí : Back.

分享 : Fēn Xiǎng : To Share.

浮动 : Fú Dòng : Floating.

复原 : Fù Yüán : Undo / Restore.

复制 : Fù Zhì : Copy / Duplicate.

关闭 : Guān Bì : Close.

剪贴簿 : Jiǎn Tiē Bù : Clipboard.

简体字 : Jiǎn Tǐ Zì : Simplified Chinese Character.

剪下 : Jiǎn Xià : Cut.

诀窍 : Jüé Qiào : Tips.

拼音 : Pīn Yīn : Phonetic Romanization.

启用 : Qǐ Yòng : Ok / To Start Using / To Enable.

取消 : Qǚ Xiāo : Cancel.

全选 : Quán Xuǎn : Select All.

手写 : Shǒu Xiě : Handwriting.

台湾 : Tái Wān : Taiwan.

调整大小 : Tiáo Zhěng Dà Xiǎo : Resize.

贴上 : Tiē Shàng : Paste.

完成 : Wán Chéng : Done / To complete / To accomplish.

文字编辑 : Wén Zì Biān Jí : Text Editing.

下一种语言 : Xià Yī Zhǒng Yǚ Yán : Next Language.

选取 : Xüǎn Qǚ : Select / Choose.

要开始手写繁体中文 : Yào Kāi Shǐ Shǒu Xiě Fán Tǐ Zhōng Wén : Do you want to begin handwriting traditional Chinese characters?

已固定 : Yǐ Gù Dìng : Pinned.

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注音 : Zhù Yīn ：Phonetic Notation Character BoPoMoFo.

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<< Back to Study Chinese Language 1

All File Access In Android Text Editors 2

These text editor or code editor are need to allow in All file access settings ( Storage Permission for file management ).

Code Studio by ALIF Technology

At the first time using save, open and other file manager function after app installed.

1. Open Code Studio app. 
   
   
   
2. Then tap "File manager / Folder" icon in the bottom. Then tap "Allow file access" button in the centre.
   
3. To found "Code Studio", swap to the bottom if need it.

   
4. Tap the "Code Studio not allowed" row 

   

   
   
5. Tap the slide on the right side of "Allow access to manage all files".  Then press Android back button.
   
   

   

   Turn "Allow access to manage all files" off in "Code Studio All file access" screen.

   

   Turn "Allow access to manage all files" on at "Code Studio All file access" screen.
   

   
   


 
6. Ensure the "Code Studio Allowed" has written. Then press arrow back button in the left "All file access".

   

   
   
7. Then folder and file list will display and ready to work.

    

   
   

QuickEdit Text Editor by Rhythm Software

1. At the first time open the QuickEdit Text Editor. You will see "All files access permission" dialog box. Tap on "OK" ( on the bottom right side ).
   
2. Tap on "Allow access to manage all files" slide. 

   

   Before "Allow access to manage all files" on.

   
   

   

   After "Allow access to manage all files" on.

3. Then press Android 'Back' button. Then you arrive at Code Editor home screen. 
   
   
   

NMM File Manager / Text Edit by maok

1. Slide your finger downwards starting from the top right side of the screen until the center right side of the screen.
   
   
2. Slide the "drawer handle ( short slim pipe bar )" downwards on the center of the screen.
   
3. Tap the "Settings" icon.
   
4. Swap downward if need it, to found "Apps" setting row.
   
5. Tap "Apps" setting row.
   
6. Tap "Special app access" row.
   
7. Tap "All file access" row.
   
8. Swap downward if need it, to found "NMM" row.
   
9. Tap "NMM Not allowed" row.
   
10. See "Allow access to manage all files" slide off.
    
11. Tap on "Allow access to manage all files" slide. Then tap "left arrow" on the top left corner.
    
12. NMM app is opened and ready to work.
    

Notes

• To maximise of your productivity, you can change the preference according with the requirements of your everyday work.
• This tutorial test and practise in RealMe smartphone. The tutorial step may different within each smartphone.

<< go to  Learn Android Apps Development

Bibliography

https://support.oppo.com/

https://userguide.one.nz/

https://www.forbes.com/

https://www.pcmag.com/

https://www.realme.com/

https://www.samsung.com/

Specialist Tools

• Al Cleaner - Storage Cleaner by GRIMLAX TRADE, S.L.
• Al SnapOCR : Text OCR Scanner by Blossgraph.
• Audiobook by Anvaysoft.
• AudioLab Audio Cutter & Editor by HitroLab - Mp3 Audio Editor and Ringtone Maker Dev.
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• Moka POS - Aplikasi Kasir by PT. GoTo Gojek Tokopedia Tbk.
• ocrX : Image to Text Al Scanner by Aculix Technologies LLP.
• Phone Cleaner - A Cleaner byBrain Trust.
• Picsart Photo Editor, Video by PicsArt, Inc.
• Photo Editor, Filters - Lumii by InShot Video Editor.
• Shell Script Editor by ALIF Technology.
• Slidebox - Photo Cleaner by Slidebox LLC.
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• SNOW - Al Profile by SNOW Corporation.
• Squid : Take Notes , Markup PDFs by Steadfast Innovation , LLC.
• Tasks by Google LLC.
• TeX Editor powered by: EMG.
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• Video Editor VideoShow Pro by VIDEOSHOW Video Editor & Maker.
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• Xero Accounting for business by Xero Accounting.
• YesWriter - Writing, Notes by DragonNest
• Zoho Books - Accounting App by Zoho Corporation.

NOTES

* The above list only for suggestion list.

* Use the only certain apps that match to your work requirements.

Mental Math Multiply Between 11 And 19

Example One

19 × 15 = ...

First Step

Sum of first addend number with ones of second addend number.

19 + 5 = 24

Second Step

Add zero at the last digit of the sum number from first step. Because more than tens number multiply with more than tens number equal hundred.

19 + 5 = 240

Third Step

Multiplying ones digit from each addend.

9 × 5 = 45

Fourth Step

Adding the sum number from second step with the sum number from third step.

240 + 45 = 285

Example Two

Practice by yourself of this example!

18 × 14 = ...

Bibliography

https://www.splashlearn.com/

https://www.twinkl.com/

Mental Math In Subtraction Rounding Base Ten Form Number

Previous Requirement Lessons

• Basic Number Operation Vocabulary 1

• Number Place Value In Mathematics

Example ( Find The Difference Number )

55 - 19 = ...

• Minuend number ( top digit ) in this example is 55.
• Subtraction sign is ( - ).
• Subtrahend number ( lower digit ) in this example is 19.
• Difference number in this example is ( ... )

First Step

Rounding the subtrahend number to the nearest tens of base ten form number. In this example we rounding 19 to 20. Then keep in the mind the additional number is 1.

55 - ( 19 + 1 ) = ...

55 - 20 = ...

Second Step

Subtract the subtrahend number from the minuend number to get difference number. In this example 20 ( subtrahend number ) from 55 ( minuend number ).

55 - 20 = 35

Third Step

Add the difference number by additional number from First Step. In this example add 35 to 1.

55 - 20 = 35 + 1

55 - 20 = 36

Fourth Step

Return the subtrahend number as the number in the question. In this example the subtrahend number return from 20 to 19.

55 - 19 = 36

Bibliography

https://byjus.com/

https://www.ck12.org/

https://www.mathnasium.com/

https://www.splashlearn.com/

Mental Math In Multiplication By Nine

Previous Requirement Lessons

• Number Place Value In Mathematics

• Number Place Value

• Basic Number Operation Vocabulary 1

• Vertical Subtraction ( with regrouping ).

Multiplication in mathematics is using the repeated addition. Multiples of 9 are any number you get ( the products ) from multiplying 9 with integer ( whole number ). 

Multiple 1 To 10 With Nine

Question

1 × 9 = ...
2 × 9 = ...
3 × 9 = ...
4 × 9 = ...
5 × 9 = ...
6 × 9 = ...
7 × 9 = ...
8 × 9 = ...
9 × 9 = ...
10 × 9 = ...

First Step

Write 0 at the left of multiplier number.

01 × 9 = ...

Second Step

Write 0 in the result ( at the right side of equal sign notation ) because every number multiple by 0 get zero. This zero number place in the tens number place value.

01 × 9 = 0 ...

Third Step

Multiply the multiplier number with multiplicand number. Write the nine.

01 × 9 = 09

Fourth Step

Write 0 at the left of multiplier number. in the second row result, write a number after  the number from the previous row ( that is 1 ) as tens number place value. Then write a number before the number from the previous row ( that is 8 ) as ones number place value. So the result is eighteen.

01 × 9 = 09

02 × 9 = 18

Fifth Step

Write 0 at the left of multiplier number. in the third row result, write a number after  the number from the previous row ( that is 2 ) as tens number place value. Then write a number before the number from the previous row ( that is 7 ) as ones number place value. So the result is twenty seven.

01 × 9 = 09

02 × 9 = 18

03 × 9 = 27

Next Step

Repeat the fifth step until all question rows is finished.

01 × 9 = 09

02 × 9 = 18

03 × 9 = 27

04 × 9 = 36

05 × 9 = 45

06 × 9 = 54

07 × 9 = 63

08 × 9 = 72

09 × 9 = 81

10 × 9 = 90

Result

Erase each zero in the first digit of multiplier.

1 × 9 = 9

2 × 9 = 18

3 × 9 = 27

4 × 9 = 36

5 × 9 = 45

6 × 9 = 54

7 × 9 = 63

8 × 9 = 72

9 × 9 = 81

10 × 9 = 90

Multiply Every Digit With Nine

Example

27 × 9 = ...

Number factor are:

• Multiplicand number is 27.
• Multiplier number is 9.

The mental math steps:

1. Multiply the number by 10:
   27 × 10 = 270
2. Subtract the result number from previous step by the original number ( multiplicand number ).
   270 - 27 = 243

Bibliography

https://byjus.com/

https://www.ck12.org/

https://www.splashlearn.com/

https://www.vedantu.com/

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