Addition of Integers: Exercise (1)
Integers 7th Math
Addition of Integers: Exercise (1)
Addition of Integers having Similar Sign
Rules to Add Integers having Similar Sign : Do the following to add integers having similar sign
(i) Forget the sign of integers
(ii) Add them using simple method of addition
(iii) Put the common sign before the integers
Addition of Integers having Positive Signs
(A) Add the following positive integers
Question (1) 5 + 1
Solution : Given, 5 + 1
= 5 + 1 = 6
Thus, Answer = 6
[Because the common sign of both of the given integers is positive (+), so the sign of answer is also positive (+). No sign has been assign before the answer, this means sign of answer is positive (+)]
Question (2) 6 + 5
Solution : Given, 6 + 5
= 6 + 5 = 11
Thus, Answer = 11
Question (3) 7 + 5
Solution : Given, 7 + 5
= 7 + 5 = 12
Thus, Answer = 12
Question (4) 9 + 2
Solution : Given, 9 + 2
= 9 + 2 = 11
Thus, Answer = 11
Question (5) 12 + 14
Solution : Given, 12 + 14
= 12 + 1 4 = 26
Thus, Answer = 26
Question (6) 5 + 4 + 3
Solution : Given, 5 + 4 + 3
= 5 + 4 + 3
= 12
Thus, Answer = 12
Question (7) 6 + 5 + 4
Solution : Given, 6 + 5 + 4
= 6 + 5 + 4 = 15
Thus, Answer = 15
Question (8) 7 + 6 + 5 + 4
Solution : Given, 7 + 6 + 5 + 4
= 7 + 6 + 5 + 4
= 22
Thus, Answer = 22
Question (9) 8 + 7 + 6 + 5 + 4
Solution : Given, 8 + 7 + 6 + 5
= 8 + 7 + 6 + 5
= 26
Thus, Answer = 26
Question (10) 9 + 10 + 11 + 12
Solution : Given, 9 + 10 + 11 + 12
= 9 + 10 + 11 + 12
= 42
Thus, Answer = 42
Addition of Integers having Negative Signs
(B) Add the following negative integers
Question (1) Add – 2 and – 1
Solution : Given, Add – 2 and – 1
Procedure to add negative integers
(i) Forget the sign of integers, and add them
= 2 + 1 = 3
(ii) Put the common sign before the result
Since, both of the given integers have – ve (negative) sign common
Thus, result = – 3
Thus, Answer = – 3
Question (2) Add –5 and – 6
Solution : Given, – 5 and – 6 are to be added
(i) Forget the sign of integers, and add them
= 5 + 6 = 11
(ii) Put the common sign before the result
Since, both of the given integers are negative, this means that their common sign is –ve (negative)
Thus, result = – 11
Thus, Answer = – 11
Question (3) Add – 11 and – 10
Solution : Given, – 11 and – 10 are to be added
Procedure to add given two negative integers
(i) Forget the sign of integers, and add them
(ii) Put the common sign before the result
Thus, after omitting the sing, given integers are 11 and 10
= 11 + 10 = 21
Since both of the given integers are negative, i.e. their common sign is negative,
Thus, Answer = – 21
Question (4) Add – 5 and – 10
Solution : Given, – 5 and – 10 are to be added
= 5 + 10 = 15
And, since their common sign is negative
Thus, Answer = – 15
Question (5) Add – 4 and – 8
Solution : Given, – 4 and – 8 are to be added
Procedure to add given two negative integers
Add both of the negative integers after forget their sign, and put the common sign (negative sign) before the result.
= 4 + 8 = 12
And, Answer = – 12
Question (6) – 5 + (–11)
Solution : Given, – 5 + (–11)
Procedure to add given two negative integers
Add both of the negative integers after forget their sign, and put the common sign (negative sign) before the result.
Thus, – 5 + (–11)
Adding of given integers after omitting their sign.
= 5 + 11 = 16
And Answer = – 16
Question (7) – 2 + (– 6)
Solution : Given, – 2 + (– 6)
Procedure to add given two negative integers
Add both of the negative integers after forget their sign, and put the common sign (negative sign) before the result.
Adding of integers are omitting their sign
= 2 + 6 = 8
Thus, result = – 8
(negative sign, which is common in the given integers, is added in the result)
Thus, Answer = – 8
Question (8) –9 + ( –10) + (– 2)
Solution : Given, –9 + ( –10) + (– 2)
Adding of integers are omitting their sign
= 9 + 10 + 2 = 21
And, since negative is the common sign of given integers,
Thus, result = – 21
Thus, Answer = –21
Question (9) –10 + (–11) + (– 9) + (–5)
Solution
Given, –10 + (–11) + (– 9) + (–5)
Adding the given integers after omitting their sign
= 10 + 11 + 9 + 5 = 35
= – 35 Answer
(Because negative is the common sign of given integers, so result is negative)
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