:
Steps: 1 Mark
Result: 1 Mark
Given: Total Amount Andy had = Rs. 1540
Total amount spendby him
= Rs. 250 + Rs. 115 = Rs. 365
Total amount left = (Total Amount Andy had) - (Total amount spendby him)
$\Rightarrow$Total amount left = Rs. 1540 - Rs. 365
= Rs. 1175
Hence, the total amount leftwith Andy is Rs.1175.

:
Application: 1 Mark
Steps: 1 Mark
Result: 1 Mark
(i) Marks given for one correct answer = 4
So, marks given for 9 correct answers
= 4 × 9 = 36
Marks given for one incorrect answer = – 2
So, marksfor 6 (15 – 9) incorrect answers
= (–2) × 6 = –12
Therefore, Gurpreet’s total score
= 36 + ( –12) = 24
(ii) Marks given for one correct answer = 4
So, marks given for 5 correct answers
= 4 × 5 = 20
Marks given for one incorrect answer
= (–2)
So, marks for 10 (15 – 5) incorrect answers = (–2) × 10 = –20
Therefore, her friend’s total score
= 20 + ( –20) = 0

:
Definition: 1 Mark
Integers are the set of whole numbers and their negatives. Integers greater than zero are called positive integers while integers less than zero are called negative integers.

:
Steps: 2 Marks
Result: 1 Mark
It is given that, in a test
Marks given for each correct answer = +2
Marks given for each wrong answer = ( -1 )
Marks obtained by 12 correct questions = 12 × 2 = 24
Marks obtained by student = 21
So, total negative marks = 24 - 21 = 3
So,the total number of incorrect questions = 3$÷$1 = 3
Total number of questions he attempted= Number of correct questions + number of incorrect question
= 12 + 3 = 15
So, the total number of questions the student attempted is 15.

:
Total Marks: 1 Mark
Minimum Marks:1 Mark
The marks obtained by the student are
= 20, 12, (-4)
The total overall marks = 20 + 12 + (-4)
= 20 + 12 - 4
= 32 - 4
= 28
Given that
A student needs to score 40 in order to pass.
So, the number of marks the student needs to get on the 4th test to pass = 40 - 28 = 12
The student needs to score 12 marks in the 4th test to pass.

Answer: Option A. ->
:

As we know that the product of two negative integers is always positive. Hence, when we multiply 12 negative integers, we can treat these 12 integers like 6 pairs of negative integers. Each pair will give us a positive integer. Hence the overall multiple will be a positive integer.

Answer: Option A. ->
:

Definition: 1 Mark
Example: 1 Mark
The word "commutative" comes from "commute" or "move around", so the Commutative Property is the one that refers to moving stuff around. 
So, if we add any number of integers in any order the result will be the same.
For addition, the rule is "a + b = b + a".
Example
2 + 3 = 3 + 2 = 5.

Answer: Option A. ->
:

Ascending Order : 1 Mark
Representation on number line : 1 Mark
Integers in ascending order: (-5), (-4), (-1), 2, 5

Answer: Option A. ->
:

Concept: 1 Mark
Result: 1 Mark
The result will be a negative integer as multiplication of one negative and one positive integer will result in a negative integer.
(a $÷$ b) = + integer
$(+)\times (-)=(-)$ integer

Answer: Option A. ->
:

Each option: 1 Mark
(a) We first move to the right of 0 by 5 steps reaching 5. Then we move 3 steps to the left of 5 reaching 2.
 
 We get, $(+5)+(-3)=2$
(b) We want to know an integer which is 5 less than 3 for that we need to start from 3 and move to the left by 5 steps and obtain –2 as shown below:
 
(c) We want to know the integer which is 4 more than –1. So, we start from –1 and proceed 4 steps to the right of –1 to reach 3 as shown below: