KnowledgeBoat Logo
|
OPEN IN APP

Chapter 1

Integers - Exercise 1(E)

Class - 7 RS Aggarwal Mathematics Solutions



Exercise 1(E)

Question 1

By how much does 5 exceed -5?

Answer

To find how much one number exceeds another, we subtract the smaller number from the larger one:

5 - (-5)
= 5 + 5
= 10

The answer is 10

Question 2

How much -7 less than -1?

Answer

We need to find the difference between −1 and −7.

So we calculate:

(-1) - (-7)
= -1 + 7
= 6

The answer is 6

Question 3

What must be subtracted from 7 to get -6?

Answer

Let the required number be x.

7 - x = -6
To solve for x, we rearrange:
x = 7 - (-6)
x = 7 + 6
x = 13

The answer is 13

Question 4

What must be subtracted from -1 to get -19?

Answer

Let the required number be x

(-1) - x = -19
Rearrange to solve for x:
x = -1 - (-19)
x = -1 + 19
x = 18

The answer is 18

Question 5

The sum of two integers is -11. If one of them is 5, then find the other.

Answer

Let the two integers be p and q.

Given,

p = 5

p + q = -11

Substitute p in the below equation:

p + q = -11
5 + q = -11 \hspace{2cm}[Substituting p]
q = -11 - 5 \hspace{2.1cm}[Solve for q]
q = -(11 + 5)
q = -16

The answer is -16

Question 6

Add the product of (-13) and (-17) to the quotient of (-187) and 11.

Answer

Calculate the product of (-13) and (-17):

(-13) x (-17) = 221 \hspace{5cm}(Negative x Negative = Positive)

Calculate the quotient of (-187) and 11:

(-187) ÷ 11 = -17 \hspace{5cm}(Negative ÷ Positive = Negative)

Now add them together:

221 + (-17)
= 221 - 17 = 204

The answer is 204

Question 7

A shopkeeper bought a pen for ₹75, a book for ₹240 and a pencil box for ₹46. He sold the pen for ₹81, book for ₹255 and the pencil box for ₹40. What was his gain or loss?

Answer

Given:

Cost Price (CP) of pen = ₹75
Cost Price (CP) of book = ₹240
Cost Price (CP) of pencil box = ₹46
∴ The total Cost Price(CP) = 75 + 240 + 46 = ₹361

Selling Price of pen = ₹81
Selling Price of book = ₹255
Selling Price of pencil box = ₹40
∴ The total Selling Price(SP) = 81 + 255 + 40 = ₹376

Since SP is greater than CP, it is a gain.

Gain = SP - CP
Gain = 376 - 361 = 15 \hspace{1cm}[Substituting the values of total SP and total CP]

∴ The shopkeeper gains ₹15

Question 8

A man starts from his home and drives 169 km to the East and then 192 km to the West. How far is he from his home finally and in which direction?

Answer

Let East be positive direction so West will be negative direction.

Given:

Distance travelled towards East = 169 km
Distance travelled towards West = -192 km

Total displacement = Distance travelled towards East + Distance travelled towards West

By substituting the values, we get

Total displacement = 169 + (-192)

= 169 - 192 = -23

The negative sign indicates that he is in West direction.

∴ He is 23 km to the West of his home.

Question 9

During a month, the average day temperature of a desert region was 43°C and the average night temperature was -6°C. Find the difference between the average day temperature and the average night temperature.

Answer

Given:

Average day temperature = 43°C
Average night temperature = -6°C

Difference = Average day temperature - Average night temperature

By substituting the values, we get

Difference = 43 - (-6)

= 43 + 6 = 49

∴ The difference between the average day and the average night temperature = 49°C

Question 10

Radhey bought 4 pairs of jeans at ₹1256 each . How much did he pay for the jeans in all?

Answer

Given:

Number of pairs of jeans = 4
Cost of 1 pair of jeans = ₹1256

Total cost = Number of pairs x Cost of 1 pair

By substituting the values, we get

Total cost = 4 x 1256 = ₹5024

∴ The total amount he paid is ₹5024

Question 11

Mathew had no money to pay for his house rent of ₹14240. His 5 friends decided to contribute equally to pay for the rent. How much will each friend pay?

Answer

Given:

Total house rent = ₹14240
Number of friends = 5

Amount paid by each friend = Total house rent ÷ Number of friends

By substituting the values, we get:

Amount paid by each friend = 14240 ÷ 5 = 2848

∴ Each friend contributes ₹2848

Question 12

A class of 36 students contributed ₹540 each for the picnic. Out of these, 7 students decided not to go. They were returned ₹490 each. What amount was spent on the picnic?

Answer

Given:

Total number of students = 36
Contribution per student = ₹540

Total amount collected = 36 x 540 = 19440

Number of students who did not go = 7
Amount returned per student = ₹490

Total amount returned = 7 x 490 = 3430

Amount spent on picnic = Total amount collected - Total amount returned

By substituting the values, we get:

Amount spent on picnic = 19440 - 3430 = 16010

∴ The amount spent on the picnic = ₹16010

PrevNext