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THE NEW STUDENT'S  REFERENCE   WORK                                    2145

Add rapidly by lines and columns:

8 +  5  +  3  + 4  +  6  =

5 + 4  +  6  + 9  +  2  =

2 +  7  +  8 +  5  +  4  =

3 +  9  +  4 +  6  +  8  = 7  + 4 +  5  +  7  +  3  =

4 +  6  +  7  +  8  +  2  =

+      +       +       +       =

A chart like the above demands the pupils7 close attention and ready response, if the teacher will point to a series of numbers in rapid succession.

Objective work in addition after 10 has been taught, should gradually give way to method.

Three classes of examples should be taught:

1.   Where the sum of the units is less than 10,

as 22+4; 33+5; 64+3, etc.

2.   Where the sum of the units exactly equals 10,

as 22+8; 33+7; 64+6, etc.

3.   Where the sum of the units exceeds 10,

as 22+9; 33+8; 64+9, etc.

Extend this work to numbers of more than two places in exactly the same way, emphasizing method of work.

428             486              596              482              825              645

351             214              678              675              642              547

725             826

779             700            1274

Add 425          In adding long columns it is often found convenient to

638   write the sum of each column, placing the right-hand figure

764  under the column added.

825          In case of error, it enables one to find the mistake with

655   less difficulty. 124

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