MCQ on Direct and Indirect Proportions for Class 8
Class 8 Maths Chapter 13 Direct and Indirect Proportions MCQ
MCQ of Direct and Indirect Proportions Class 8
I. Choose the correct answer.
Question 1.
A car covers a distance of 60 km by using 4 litre petrol, then it covers __________ km by using 0.5 lit petrol.
A) 15
B) 25
C) 30
D) 7.5
Answer:
D) 7.5
Question 2.
Given ‘x’ and ‘y’ are in direct proportion, then we say __________ .
A) x ∝ y
B) \(\frac{x}{y}\) = k
C) x = ky
D) all the above
Answer:
D) all the above
Question 3.
Which of the following are in direct proportion ?
A) Number of pages in book, and its weight
B) Mass of food grains, number of people food taken from them
C) Height of a man and his age
D) All the above
Answer:
A) Number of pages in book, and its weight
Question 4.
Which of the following are not a direct proportion ?
A) Number of kilometers run, volume of fuel spent
B) Number of people employed to work, number of days taken to complete the job.
C) Cost of paint, area to be painted.
D) None of the above.
Answer:
B) Number of people employed to work, number of days taken to complete the job.
Question 5.
A 15 m object gives a shadow of 5m, then how long another object gives 9 m shadow at same time, place ?
A) 3 m
B) 27 m
C) 14 m
D) 29 m
Answer:
B) 27 m
Question 6.
Cost of 5 m of cloth is ₹ 320 /-, then cost of 3m, 6m, 9m pieces are ________ (of same cloth)
A) ₹ 64/-, ₹ 120/-, ₹ 192/-
B) ₹ 192/-, ₹ 320/-, ₹ 480/-
C) ₹ 192/-, ₹ 384/-, ₹ 576/-
D) none
Answer:
C) ₹ 192/-, ₹ 384/-, ₹ 576/-
Question 7.
y = kx ; k refers to _________ .
A) rate of change
B) proportional constant
C) ‘A’ or ‘B’
D) none
Answer:
C) ‘A’ or ‘B’
Question 8.
\(\frac{y}{x}\) = k, then y, x are in _________ .
A) direct variation
B) indirect proportion
C) either ‘A’ or ‘B’
D) ‘A’ and ‘B’
Answer:
A) direct variation
Question 9.
If a machine fills 1400 prickle packs in 3\(\frac{1}{2}\) hours, then it can fill _________ packets in 375 minutes.
A) 2800
B) 2600
C) 2400
D) 2500
Answer:
D) 2500
Question 10.
xy = k, then x, y are in_________ .
A) direct proportion
B) indirect proportion
C) either ‘A’ or ‘B’
D) ‘A’ and ‘B’
Answer:
B) indirect proportion
Question 11.
A xerox machine prints 5 copies in every 3 minutes, then it can print ________ copies in 3\(\frac{1}{20}\)hours.
A) 305
B) 503
C) 15
D) 355
Answer:
A) 305
Question 12.
X | 50 | 25 | 25 | 5 |
y | 5 | 20 | 10 | 50 |
in these which pair are not in indirect proportion ?
A) (50, 5)
B) (25, 20)
C) (25, 10)
D) (5, 50)
Answer:
B) (25, 20)
Question 13.
Which pair in the following is not in direct proportion ?
x | 100 | 500 | 10000 | 50 |
y | 2 | 10 | 200 | 5 |
A) (100, 2)
B) (500, 10)
C) (10000, 200)
D) (50, 5)
Answer:
D) (50, 5)
Question 14.
If x1 y1 = _________ , then we can say ‘x’ and ‘y’ are in inverse proportion ?
A) \(\frac{x_2}{y_2}\)
B) x2y2
C) x2 + y2
D) \(\frac{y_2}{x_2}\)
Answer:
B) x2y2
Question 15.
When the area of a rectangle is constant, its length and breadth are ________ .
A) l ∝ b
B) l ∝ \(\frac{1}{b}\)
C) l = b
D) \(\frac{l}{\mathrm{~b}}\) = k
Answer:
B) l ∝ \(\frac{1}{b}\)
Question 16.
Perimeter (P) and Side (S) of square are __________ .
A) P ∝ S
B) PS = K
C) P ∝ S-1
D) P = S
Answer:
A) P ∝ S
Question 17.
Number of Spokes (S) in a cycle wheel, and angle between Spokes (a), then their relation is _________ .
A) S + a = 360°
B) \(\frac{\mathrm{S}}{\mathrm{a}}\) = 360°
C) S + a = 90°
D) Sa = 360°
Answer:
D) Sa = 360°
Question 18.
If 15 workers build a wall in 48 hours, then __________ workers can complete it 18 hours early.
A) 57
B) 24
C) 30
D) 43
Answer:
B) 24
Question 19.
If 100 kg Biryani serves 150 members, then how much more is needed to serve 30 members are ?
A) 120 kg
B) 30 kg
C) 20 kg
D) 25 kg
Answer:
C) 20 kg
Question 20.
In a hostel, stock available for 25 students @ 400 grams per day for 32 days. After 5 students left from hostel, provisions are raised to 500 grams per day. Then the stock is sufficient for ___________ days.
A) 25
B) 32
C) 20
D) 35
Answer:
B) 32
Question 21.
Given, x ∝ y then, which of the following are true?
A) √x ∝ √y
B) x2 ∝ y2
C) 2x ∝ 2y
D) all the above
Answer:
C) 2x ∝ 2y
For the following A, R type questions from 22 to 26. Choose the answer from following options.
A) Both ‘A’ and ‘R’ are correct and ‘R’ is reason for ‘A’
B) Both ‘A’ and ‘R’ are Correct but ‘R’ is not reason for ‘A’.
C) ‘A’ is true but ‘R’ is false
D) ‘A’ is false but ‘R’ is true.
Question 22.
Assertion (A) : A train covers a distance of 60 km in one hour.
Reason (R) : Speed of above train is 60 kmph and it covers 300 km in 5 hours.
Answer:
A) Both ‘A’ and ‘R’ are correct and ‘R’ is reason for ‘A’
Question 23.
Assertion (A) : If cost of 3 kg sweet is ₹ 690/-, then cost of 6 kg sweet will be ₹ 345/-.
Reason (R) : Cost and its weight are in direct variation.
Answer:
D) ‘A’ is false but ‘R’ is true.
Question 24.
Assertion (A) : If cost of 10 gram gold is ₹ 50,000/-, then cost of 1 kg gold will be 50 lakhs.
Reason (R) : If 2 sq. meter cloth costs ₹ 250, then 5m2 same cloth will cost ₹ 625/-.
Answer:
B) Both ‘A’ and ‘R’ are Correct but ‘R’ is not reason for ‘A’.
Question 25.
Assertion (A) : If 5 m tall post gives 2m shadow, then 1 m tall post gives 40 cm shadow.
Reason (R) : Height of building and the length of shadow formed are in indirect proportion.
Answer:
C) ‘A’ is true but ‘R’ is false
Question 26.
Assertion (A) : If travel charge for 1 man and 2 womeh is ₹ 300, then travel charge for 2 men and 1 women will also ₹ 300/-
Reason (R) : Travel cost and number of persons are in direct variation.
Answer:
A) Both ‘A’ and ‘R’ are correct and ‘R’ is reason for ‘A’
II. Fill in the blanks.
1.
x | 10 | 24 | 40 |
y | 125 | 30 | P |
table showing x ∝ y, then the value of p = __________ .
Answer:
50
2. If x1y1 = x2y2 = x3y3, then x and y are in __________ proportion.
Answer:
indirect
3. If x1y2 = x2y1, then x and y are in __________ proportion.
Answer:
direct
4. A work can be completed in 4 days by 3 men, then it can be completes in __________ days by 12 men.
Answer:
1
5. A piece of wall can be constructed by 20 workers in (nine) 9 days, but 4 of them left and another 2 are available half time only. So, the work will take __________ more days to complete.
Answer:
3
6. Number of spokes in a wheel are increased from 6 to 9, then angle decreased by __________ %
Answer:
33.3%
7. Number of workers and time to complete the job are in __________ proportion.
Answer:
indirect (inverse)
8. An Independence day, Head Master of ZPHS, Atmakur arranged sweets for 280 students, at each 5, but the students attended 25% in excess. Then each Student will get __________ sweets.
Answer:
4
9. A Beverage company can fill 180 cartons such that each carton have 24 bottles. But to save money it plans to produce 216 cartons without changing its capacity. Then each carton will have __________ bottles now.
Answer:
20
10. A sweet making company requires 1 : 5 ratio of ghee and sugar. One day it used 27.5 kilos of sugar, then use of ghee o’n that day was __________ kg.
Answer:
5.5
11. x and y are in direct proportion, then \(\frac{x}{y}\) = __________
Answer:
constant
12. If xy = k (k is constant), then x and y are in direct proportion. (True / False)
Answer:
False
III. Match the following.
Question 1.
A | B |
1) Scale of a map is 1 : 250000 | a) direct proportion |
2) Number of men and number of days taken to complete work. | b) indirect proportion |
3) Cost of sweets and its weight | c) two cities are at a distance of 5 km if they are 2 cm apart. |
4) x ∝ y ;x1 = 4, x2 = 6 and y1 = 12, then y2 = __________ | d) 2 |
5) x ∝ y-1; x1 = 4, x2 = 6 and y1 = 12, then y2 = ___________ | e) 18 |
Answer:
(1, c) (2, b) (3, a) (4, e) (5, d)
A | B |
1) Scale of a map is 1 : 250000 | c) two cities are at a distance of 5 km if they are 2 cm apart. |
2) Number of men and number of days taken to complete work. | b) indirect proportion |
3) Cost of sweets and its weight | a) direct proportion |
4) x ∝ y ;x1 = 4, x2 = 6 and y1 = 12, then y2 = __________ | e) 18 |
5) x ∝ y-1; x1 = 4, x2 = 6 and y1 = 12, then y2 = ___________ | d) 2 |
Question 2.
A | B |
1) x1 = 16, y1 = 4, x2 = 8, y2 = 8, then x, y are __________ | a) \(\frac{x}{y}\) = k |
2) x1 = 16, y1 = 4, x2 = 8, y2 = 2, then x, y are ____________ | b) in indirect variation |
3) x ∝ y, then | c) xy = k |
4) x ∝ \(\frac{1}{y}\) , then | d) in direct variation |
5) x2, x are in direct proportion | e) false |
Answer:
(1, b) (2, d) (3, a) (4, c) (5, e)
A | B |
1) x1 = 16, y1 = 4, x2 = 8, y2 = 8, then x, y are __________ | b) in indirect variation |
2) x1 = 16, y1 = 4, x2 = 8, y2 = 2, then x, y are ____________ | d) in direct variation |
3) x ∝ y, then | a) \(\frac{x}{y}\) = k |
4) x ∝ \(\frac{1}{y}\) , then | c) xy = k |
5) x2, x are in direct proportion | e) false |