ADDITION. 18
equal to 1 thousand and nine hundreds. We write the 9 under the column of hundreds; and there being no other col. umn to be added, we set down the 1 thousand in thousands" place, and find the amount of the several numbers to be 1928.
22. From the preceding examples and illustrations we deduce the following
Rule.—Write the numbers so that all the units shall stand in the first column on the right hand, and all tens in the second column'; and all the hundreds in the third column; and all the thousands in the fourth column, &c.
Add, upward, all the figures in the column of units, and if the amount be less than ten, write it underneath. But, if the amount be ton or more, write down the unit figure only, and add in the figure denoting the tens with the next column.
Proceed in like manner with each column, until all are added, observing to write down the whole amount of the last column.
23. SECOND METHOD OF PROOF.-Separate the numbers to be added into two parts by a horizontal line. Add the numbers below the line, and set down their sum. Then add this sum and the number, or numbers, above the line and if their sum is equal to the first amount, the work is presumed. to be right. EXAMPLES FOR PRACTICE.. (2) OPERATION PROOF. 5 2 6 5 2 6 31 7 5 2 9 31 7 1 3 2 5 2 9 1 3 2 Ans. 1 5 0 4
Amount below the line, 9 7 8
Amount below the line added –
to that written above the line, 1 5 0 4
This is the same as the first answer obtained.
