Page 26 - Math Skill - 4

24 Maths

Missing Digits in an Addition Sum
We can find out the missing digits in the addition sum. L TTh Th H T O

Let us find out the missing digits. 2 3 2 1
Step 1: At ones place; 1 + = 5 ⇒ 5 – 1 = 4 + 5 4 6

Step 2: At tens place; + 6 = 8 ⇒ 8 – 6 = 2 6 8 5 8 5
Step 3: At hundreds place; 2 + 4 = 6

Step 4: At thousands place; 3 + = 5 ⇒ 5 – 3 = 2 L TTh Th H T O
3
1
3
2
2
2
Step 5: At ten thousands place; + 5 = 8 ⇒ 8 – 5 = 3
Step 6: At lakhs place; 2 + = 6 ⇒ 6 – 2 = 4 + 4 5 2 4 6 4
6 8 5 6 8 5
Exercise 2.1

1. Add the following.
(a) TTh Th H T O (b) TTh Th H T O (c) TTh Th H T O
3 4 9 8 2 6 8 0 2 4 2 4 0 1 4
+ 2 5 0 1 1 + 2 1 7 3 4 3 6 0 4

+ 1 2 8 9 2

(d) L TTh Th H T O (e) L TTh Th H T O (f) L TTh Th H T O

1 2 3 4 5 6 2 1 4 8 0 4 1 8 4 2 6 0
5 4 3 2 6 1 1 2 5 6 8 2 2 5 9 7 3 1
+ 5 1 2 3 4 + 0 1 3 8 4 + 1 7 1 1 3 8

2. Write the following in columns and find the sum.
(a) 212 + 26814 + 34567 (b) 4614 + 38943 + 34560

(c) 777772 + 33333 + 10345 (d) 86 + 24968 + 708936
(e) 79612 + 79638 + 78345 (f) 278117 + 439268 + 276825

3. Replace the ‘*’ with the correct digit.
(a) TTh Th H T O (b) TTh Th H T O (c) TTh Th H T O

* 4 1 2 * 1 0 0 8 * 6 4 9 3 4
+ 6 2 * 1 4 + 6 * 7 * 0 + * 1 3 * *
7 * 9 * 9 * 6 7 8 9 9 * 3 1 5

(d) L TTh Th H T O (e) L TTh Th H T O (f) L TTh Th H T O
9 * 3 4 * * 7 * 4 8 9 * * 7 8 9 2 9
+ * 4 6 2 8 6 + * 5 * * 0 5 + 5 3 * 8 3 *

9 4 * * 9 8 8 8 9 9 * 6 8 1 6 * * 1