Page 29 - ICSE Math 5

Addition and
Addition and

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Subtr
Subtractionaction

Learning Outcomes

Students will be able to learn:
 to add and subtract large numbers (up to nine digits).
 to find the missing digits.
 to estimate the sum and difference by rounding off numbers.
 to solve and frame word problems involving real life situations.

We have learnt addition and subtraction in the previous classes. Let’s learn to perform these
operations on large numbers.

Addition

We know that addition is the process of combining two or more addends to find their
sum. Addends are first arranged in columns and then added by starting from the extreme
right and proceeding towards the larger periods on the left. Now let’s learn to add larger
numbers.

Addition of Large Numbers (without carry over)

To add large numbers, start adding the digits from the ones place and then move towards the
tens, hundreds, thousands places and so on.
Example 1: Find the sum of 37,241 and 21,356. Write the sum obtained in words.

Solution: Add the columns one by one and write the sum as shown.

TTh Th H T O Top Tip

3 7 2 4 1 Two or more numbers
can be added in any order
+ 2 1 3 5 6
to find the sum.
5 8 5 9 7

So, 37,241 + 21,356 = 58,597 and it is written as fifty-eight thousand five hundred
ninety-seven in words.

Addition of Large Numbers (with carry over)

Look at the given examples to see how to add large numbers with carry over.
Example 2: Find the sum of 42,618 and 37,956. Write the sum obtained in words.

Solution: Add the columns one by one and write the carry over in each step.

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