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Example 3. Add: 3018 + 2654 + 2345
Solution.
Th H T O
Step 1. Add the ones and regroup.
1 1 1
8 + 4 + 5 = 17 ones = 1 ten 7 ones 3 0 1 8

Step 2. Add the tens and regroup. 2 6 5 4

1 + 1 + 5 + 4 = 11 tens = 1 hundred 1 ten + 2 3 4 5

Step 3. Add the hundreds and regroup.
8 0 1 7
1 + 0 + 6 + 3 = 10 hundreds = 1 thousand 0 hundreds

Step 4. Add the thousands.

1 + 3 + 2 + 2 = 8 thousands

Therefore, 3018 + 2654 + 2345 = 8017.

Adding 10, 100 and 1000 to a number

When 10, 100 and 1000 are added to a number, the digit in its tens, hundreds and
thousands place increases by 1.

Examples: a. 625 + 10 = 635
Interesting Facts
The sum of any number and zero
b. 3495 + 100 = 3595 gives the same number.

When 1 is added to a number, the
c. 7347 + 1000 = 8347 sum is the successor of the number.

Exercise 2D

1. Find the sum.

a. 2 3 5 6 b. 6 9 4 5 c. 5 4 2 9 d. 5 0 8 7

+ 4 5 3 5 + 2 0 6 9 + 2 5 8 9 + 2 8 6 4

e. 5 4 9 4 f. 3 4 5 4 g. 1 5 6 7 h. 2 5 8 7
1 7 8 7 1 7 8 3 2 4 5 9 4 7 7 4

+ 2 0 4 3 + 2 3 2 4 + 4 5 4 1 + 2 3 3 6

46 Mathematics 3