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Exploring Addition
We can add numbers in many ways. Let us learn some of them.
Expanding numbers
Example 1. Add 37 and 22.
Solution.
Break the numbers into tens First add the ones and then the tens.
and ones.
37 30 + 7 37 30 + 7
+ 22 20 + 2 + 22 20 + 2
Sum 59 50 + 9
Expanding one number
Example 2. Find 42 + 16.
Solution.
Break the smaller number into tens Add 42 and 10 first and then add the
and ones. sum obtained and 6.
42 42 42 42
+ 16 10 + 6 + 16 10 + 6
Sum 58 52 + 6
Exercise 2A
1. Find the sum by expanding the numbers.
a. 43 + 84 = b. 25 + 36 = c. 32 + 24 =
d. 34 + 44 = e. 56 + 31 = f. 45 + 23 =
2. Find the sum by expanding the smaller number.
a. 28 + 24 = b. 45 + 14 = c. 55 + 32 =
d. 43 + 21 = e. 24 + 15 = f. 71 + 26 =
39
Addition
