Mammoth Memory

Addition

Traditional method or column addition

Requires you to understand that the number such as `385` is in fact three 100’s eight 10’s and five 1’s.

Or           `300 + 80 + 5`

And this place value system is called the decimal system.

 

Remember this is better than adding pounds shillings and pence.

NOTE:

`d` = pennies = `12` pennies in a shilling

`S` = shillings = `20` shillings in a pound

`£` = Pound = `240` pence `(12xx20=240)`

 

and `8d+7d+10d=25d` or `2` shillings and `1d`

and `4S+5S+3S` and `2S` carried over is `14` shillings

 

Example 1

`398+427`

     
`3` `9` `8`
`4` `2` `7`

`8` `2` `5`

 

Answer: `=825`

To see this example step by step

Press Here

Traditional addition

Example 1

`398+427`


  3 9 8    
`+` 4 2 7    

   

 

    1      
  3 9 8   Add the ones (8 ones `+`7 ones `=`15 ones)
`+` 4 2 7   Regroup (15 ones `=`1 ten `+`5 ones)

   
      5    

 

 

  1 1      
  3 9 8   Add the tens (1 ten `+`9 tens `+`2 tens `=`12 tens)
`+` 4 2 7   Regroup (12 tens `=`1 hundred `+`2 tens)

   
    2 5    

 

  1 1      
  3 9 8   Add the hundreds (1 hundred `+`3 hundred `+`4 hundred `=`8 hundred)
`+` 4 2 7  

   
  8 2 5    

 

Answer: `=825`

 

 

 

Example 2

`365+297`

     
`3` `6` `5`
`2` `9` `7`

`6` `6` `2`

 

Answer: `=662`

To see this example step by step

Press Here

Traditional addition

Example 2

`365+297`

  3 6 5    
`+` 2 9 7    

   

 

    1      
  3 6 5   Add the ones (5 ones `+`7 ones `=`12 ones)
`+` 2 9 7   Regroup (12 ones `=`1 ten `+`2 ones)

   
      2    

  

  1 1      
  3 6 5   Add the tens (1 ten `+`6 tens `+`9 tens `=`16 tens)
`+` 2 9 7   Regroup (16 tens `=`1 hundred `+`6 tens)

   
    6 2    

 

  1 1      
  3 6 5   Add the hundreds (1 hundred `+`3 hundred `+`2 hundred `=`6 hundred)
`+` 2 9 7  

   
  6 6 2    

 

Answer: `=662`

More Info