Checking Subtraction using Addition - Grade 2 Math USA
Checking Subtraction using Addition
Here we shall check subtraction using addition. So, first we shall subtract the subtrahend from the minuend. Then we shall add the subtrahend and the difference. If subtrahend + difference = minuend, then we shall say that the subtraction is correct. Now, follow the examples for better understanding.
1. 93 – 59
Solution:
Subtract 59 from 93.
93
-59
34
The difference = 34.
Checking Subtraction using Addition:
Add the subtrahend and the difference.
59
+34
93
The sum (93) = the minuend (93).
∴ The subtraction is correct.
2. 69 – 35
Solution:
Subtract 35 from 69.
69
- 35
34
The difference = 34.
Checking subtraction using addition:
Add the subtrahend and the difference.
35
+ 34
69
The sum (69) = the minuend (69).
∴ The subtraction is correct.
3. Subtract and check each subtraction using addition.
(i) 75 - 68
(ii) 61 - 36
(iii) 34 - 29
(iv) 92 - 31
(v) 83- 49
(vi) 67 - 39
(vii) 73 - 47
(viii) 97 - 75
(ix) 46 - 42
(x) 82 – 67
Solution:
|
No.
|
Subtraction
|
Checking
|
|
(i)
|
75
-68 7 |
68
+7 75 |
|
(ii)
|
61
-36 25 |
36
+25 61 |
|
(iii)
|
34
-29 5 |
29
+5 34 |
|
(iv)
|
92
-31 61 |
31
+61 92 |
|
(v)
|
83
-49 34 |
49
+34 83 |
|
(vi)
|
67
-39 28 |
39
+28 67 |
|
(vii)
|
73
-47 26 |
47
+26 97 |
|
(viii)
|
97
-75 22 |
75
+22 97 |
|
(ix)
|
46
-42 4 |
42
+4 82 |
|
(x)
|
82
-67 15 |
67
+15 82 |
4. Find the differences and check them using addition.
(i) 836
- 685
141
(ii) 700
- 631
69
(iii) 5360
- 3168
2182
(iv) 8400
- 4116
4284
(v) 6802
- 5498
1304
(vi) 6500
- 4389
2011
Solution:
Check:
(i)
685
+ 141
826
But, the minuend = 836
Therefore, the subtraction is wrong.
Correction:
836
- 685
151
(ii)
631
+ 69
700
The sum is equal to the minuend.
Therefore, the subtraction is correct.
(iii)
3168
+ 2182
5350
But, the minuend = 5360
Therefore, the subtraction is wrong.
Correction:
5360
- 3168
2192
(iv)
4116
+ 4284
8400
The sum is equal to the minuend.
Therefore, the subtraction is correct.
(v)
5498
+ 1304
6802
The sum is equal to the minuend.
Therefore, the subtraction is correct.
(vi)
4389
+ 2011
6400
But, the minuend = 6500
Therefore, the subtraction is wrong.
Correction:
6500
- 4389
2111
Also: