MCQ Questions | Class 8 Maths Chapter 13 | Direct and Indirect proportions with Answers

MCQ | Direct and Indirect proportions Class 8

Check the below NCERT MCQ Questions for Class 8 Maths Chapter 13 Direct and Indirect proportions with Answers Pdf free download. MCQ Questions for Class 8 Maths with Answers were prepared based on the latest exam pattern. We have Provided Direct and Indirect proportions Class 8 Maths MCQs Questions with Answers to help students understand the concept very well.

Objective Question | NCERT Maths Class 8

NCERT Solutions Class 8 Maths
Book:	National Council of Educational Research and Training (NCERT)
Board:	Central Board of Secondary Education (CBSE)
Class:	8th
Subject:	Maths
Chapter:	13 Part-2
Chapters Name:	Direct and Indirect proportions
Medium:	English

Ncert Solutions for Class 8 Maths | Objective Type Questions

You can refer to NCERT Solutions for Class 8 Maths Chapter 13 Direct and Indirect proportions to revise the concepts in the syllabus effectively and improve your chances of securing high marks in your board exams.

Direct and Indirect proportions | Class 8 Maths | NCERT Solutions

Q1.	CBSE Class 8 Maths Mcq Questions If 8 men can do a piece of work in 20 days, in how many days could 20 men do the same work ?
	A. 6 days
	B. 8 days
	C. 4 days
	D. 10 days.

Ans: 8 days
Explanation:
8 × 20 = 20 × ? ⇒ ? = 8.

Q2.	CBSE Class 8 Maths Direct and Inverse Proportions Mcq Questions If an amount of food last for 40 days for 120 men, how long will it last for 80 men at the same rate ?
	A. 50 days
	B. 60 days
	C. 80 days
	D. 100 days.

Ans: 60 days
Explanation:
40 × 120 = 80 × ? ⇒ ? = 60.

Q3.	Class 8 Maths Mcq Chapter 13 If 18 women can reap a field in 7 days, in what time can 6 women reap the same field ?
	A. 15 days
	B. 21 days
	C. 30 days
	D. 36 days.

Ans: 21 days
Explanation:
18 × 7 = 6 × ? ⇒ ? = 21.

Q4.	Class 8 Maths Mcq online test 10 men can dig a trench in 15 days. How long will 3 men take ?
	A. 50 days
	B. 60 days
	C. 100 days
	D. 75 days.

Ans: 50 days
Explanation:
10 × 15 = 3 × ? ⇒ ? = 50.

Q5.	Class 8 Maths Mcq with answers 3 lambs finish eating turnips in 8 days. In how many days will 2 lambs finish them ?
	A. 6
	B. 8
	C. 10
	D. 12.

Ans: 12
Explanation:
3 × 8 = 2 × ? ⇒ ? = 12.

Q6.	Learn Cbse Class 8 Maths Mcq 6 pipes are required to fill a tank in 1 hour. How long will it take if only 5 pipes of the same type are used ?
	A. 75 minutes
	B. 72 minutes
	C. 80 minutes
	D. 90 minutes.

Ans: 72 minutes
Explanation:
6 × 60 = 5 × ? ⇒ ? = 72 minutes.

Q7.	Mcq Class 8 Maths Chapter 13 40 cows can graze a field in 16 days. How many cows will graze the same field in 10 days ?
	A. 60
	B. 64
	C. 80
	D. 75.

Ans: 64
Explanation:
40 × 16 = ? × 10 ⇒ ? = 64.

Q8.	Mcq for Class 8 Maths Chapter 13 If x = ky and when y = 4, x = 8 then k =
	A. 1
	B. 2
	C. 3
	D. 4.

Ans: 2
Explanation:
8 = 4k ⇒ k = 2.

Q9.	Mcq Questions for Class 8 Maths with answers pdf Chapter 13 The constant of variation, if x ∝ y, from the following table is
	A. 1
	B. 2
	C. 3
	D. 4.

Ans: 3
Explanation:
2 × 3 = 6, 4 × 3 = 12,
5 × 3 = 15, 7 × 3 = 21.

Q10.	Mcq Questions for Class 8 Maths with answers pdf download x and y vary inversely with each other. If x – 15 when y = 6, then the value of x when y = 15 is
	A. 2
	B. 4
	C. 5
	D. 6.

Ans: 6
Explanation:
15 × 6 = ? × 15 ⇒ ? = 6.

Q11.	Ncert Class 8 Maths Mcq Chapter 13 If x = 20 and y = 40, then x and y are:
	A. Directly proportional
	B. Inversely proportional
	C. Neither directly nor inversely proportional
	D. Cannot be determined

Ans: Directly proportional
Explanation:
x = 20 and y = 40
Clearly, 40 = 2 × 20
y = 2x
y ∝ x, where 2 is the proportionality constant.

Q12.	Ncert Class 8 Maths Mcq Questions If x = 15 and y = 1/30, then x and y are:
	A. Directly proportional
	B. Inversely proportional
	C. Neither directly nor inversely proportional
	D. Cannot be determined

Ans: Directly proportional
Explanation:
x = 15, y = 1/30
1/30 = 1/(2 × 15)
y = 1/2x
Hence, y ∝ 1/x, where 1/2 is the proportionality constant.

Q13.	CBSE Class 8 Maths Chapter 13 Mcq If x and y are directly proportional, then which of the following is correct?
	A. x + y = constant
	B. x – y = constant
	C. xy = constant
	D. x/y = constant

Ans: x/y = constant
Explanation:
x ∝ y
x = ky
k = x/y, where k is a constant.

Q14.	CBSE Class 8 Maths Chapter 13 Mcq Questions If x and y are inversely proportional, then:
	A. x + y = constant
	B. x – y = constant
	C. xy = constant
	D. x/y = constant

Ans: xy = constant
Explanation:
x ∝ 1/y
x = k/y
xy = k
Where k is a constant.

Q15.	CBSE Class 8 Maths Direct and Inverse Proportions Mcq If x ∝ y and x₁= 5, y₁ = 210 and x₂ = 2, then find y₂ ?
	A. 200
	B. 84
	C. 99
	D. 70

Ans: 84
Explanation:
x ∝ y
x = ky
x/y = k
x₁/y₁ = x₂/y₂
5/210 = 2/y₂
y₂ = 84

Q16.	CBSE Class 8 Maths Mcq Questions If the weight of 12 sheets of thick paper is 40 grams, how many sheets of the same paper would weigh 2500 grams?
	A. 750
	B. 800
	C. 850
	D. 950

Ans: 750
Explanation:
For 12 sheets, weight of paper is 40 grams
Let number of sheets for 2500 is x.
Using direct proportion concept:
12/40 = x/2500
x = (12 × 2500)/40
x = 750

Q17.	CBSE Class 8 Maths Direct and Inverse Proportions Mcq Questions The scale of a map is given as 1 : 300. Two cities are 4 km apart on the map. The actual distance between them is:
	A. 1000 km
	B. 1100 km
	C. 1200 km
	D. 1300 km

Ans: 1200 km
Explanation:
1 : 300 = x : y
1/300 = 4/y
y = 4 x 300 = 1200
Hence, the distance between the two cities is 1200 km.

Q18.	Class 8 Maths Mcq Chapter 13 If x and y are inversely proportional, then which one is true?
	A. x₁/y₁ = x₂/y₂
	B. x₁/x₂ = y₁/y₂
	C. x₁/x₂ = y₂/y₁
	D. x₁.x₂ = y₁.y₂

Ans: x₁/x₂ = y₂/y₁
Explanation:
x ∝1/y
x = k (1/y)
xy = k
x₁y₁=x₂y₂
x₁/x₂=y₂/y₁

Q19.	Class 8 Maths Mcq online test 6 pipes are required to fill a tank in 1 hour 20 minutes. If we use 5 such types of pipes, how much time it will take to fill the tank?
	A. 120 minutes
	B. 96 minutes
	C. 80 minutes
	D. 85 minutes

Ans: 96 minutes
Explanation:
For 6 pipes, it takes 1 hour 20 minutes
1 hour 20 minutes = 60 + 20 = 80 minutes
For 5 pipes, let the time taken be x.
This is inverse proportion case:
80 × 6 = x × 5
x = 480/5 = 96

Q20.	Class 8 Maths Mcq with answers If 12 workers can build a wall in 50 hours, how many workers will be required to do the same work in 40 hours?
	A. 10
	B. 13
	C. 14
	D. 15