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Everyday MathematicsColumn Addition

Column AdditionColumn addition involves:Recording numbers in place-value columns;Adding in place-value columns; andMaking and moving groups of 1s, 10s, 100s, and so on.

Everyday Mathematics

Column AdditionSolve: 379 + 562We set up the problem by writingthe numbers in their place-value columns.H = hundredsT = tensO = ones

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Column AdditionSolve: 379 + 562We add the digits in each column,keeping the sums separate in theplace-value columns.It doesnt matter if we start at theleft or at the right.

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Column AdditionSolve: 379 + 562We make adjustments so eachcolumn has only one digit. Thiscan be done in any order, but itsmost efficient to start with theones place-value column.

HTO379+56281311Everyday Mathematics

Column AdditionSolve: 379 + 562The 11 in the ones columnrepresents 11 ones.Remember: 11 = 10 + 1Move 10 ones to the tens column as 1 ten.

HTO379+56281311Everyday Mathematics

Column AdditionSolve: 379 + 562Now we can rewrite the answer:There are still 8 hundreds.There are 14 tens (13 tens + 1 ten = 14 tens).There is only 1 one left in the ones column.Remember that we moved 10 onesto the tens column as 1 ten.

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Column AdditionSolve: 379 + 562Now lets adjust the tens column.The 14 in the tens columnrepresents 14 tens.14 tens = 10 tens + 4 tensRemember: 10 tens is 1 hundred.Move 10 tens to the hundredscolumn as 1 hundred.

HTO379+562813118141Everyday Mathematics

Column AdditionSolve: 379 + 562Now lets adjust the tens column.The 14 in the tens columnrepresents 14 tens.14 tens = 10 tens + 4 tensRemember: 10 tens is 1 hundred.Move 10 tens to the hundredscolumn as 1 hundred.

HTO379+562813118141941Everyday Mathematics

Column AdditionNow we can rewrite the answer:There are now 9 hundreds in thehundreds column (8 hundreds + 1hundred = 9 hundreds).There are only 4 tens left in thetens column. (Remember that wemoved 10 tens to the hundreds column.)There is still 1 one in the ones column.Since we now have exactly one digitin each of the place-value columns, our work is done.HTO379+562813118141 4 Everyday Mathematics19

Column Addition379 + 562 = 941

HTO379+562813118141941Everyday Mathematics

Column AdditionWhen children use column addition they practice a variety of skillsrelated to number sense and algebraic reasoning. For example:Writing numbers according to the place value of the digits;Renaming numbers in different ways; andMaking 10s and 100s, and moving between place-value columns.Some teachers introduce column addition as a step between childrensinvented algorithms and the U.S. traditional addition algorithm.Column addition can be explained with language and representationsthat make sense in terms of place value.Everyday Mathematics