Page No.9.19, Ratio Proportion And Unitary Method, Class 6, Maths RD Sharma Solutions | RD Sharma Solutions for Class 6 Mathematics PDF Download

Question 1: A ratio equivalent of 2 : 3 is

(a) 4 : 3
(b) 2 : 6
(c) 6 : 9
(d) 10 : 9

ANSWER: (c) 6 : 9
2 : 3 is equivalent to 6 : 9. (Dividing by 3)

Question 2: The angles of a triangle are in the ratio 1 : 2 : 3. The measure of the largest angle is
(a) 30°
(b) 60°
(c) 90°
(d) 120°

ANSWER: (c) 90^o
Sum of all the angles of a triangle = 180^o

Question 3: The sides of a triangle are in the ratio 2 : 3 : 5. If its perimeter is 100 cm, the length of its smallest side is
(a) 2 cm
(b) 20 cm
(c) 3 cm
(d) 5 cm

ANSWER: (b) 20 cm
Length of the smallest side

Disclaimer: In actual terms, the sides of a triangle cannot be in the ratio 2 : 3 : 5.
Because, to form a triangle, the sum of two sides must be greater than the third side.
Here, the sum of two sides of the triangle is equal to the third side. 

ANSWER: (a) 63
Let the larger number be x.
Then

Question 5: Two ratio 384 : 480 in its simplest form is
(a) 3 : 5
(b) 5 : 4
(c) 4 : 5
(d) 2 : 5

ANSWER: (c) 4 : 5 

384/480 = 4/5 (Dividing the denominator and numerator by 96)

Question 6: If A, B, C,divide Rs 1200 in the ratio 2 : 3 : 5, then B's share is
(a) Rs 240
(b) Rs 600
(c) Rs 380
(d) Rs 360

ANSWER: (d) Rs. 360

Question 7: If a bus travels 126 km in 3 hours and a train travels 315 km in 5 hours, then the ratio of their speeds is
(a) 2 : 5
(b) 2 : 3
(c) 5 : 2
(d) 25 : 6

ANSWER: (b) 2 : 3

Ratio of their speeds = 42 : 63 = 2 : 3 

ANSWER: (c) 69

If the number of male employees is 115, let the number of female employees be x.

According to the question:

Question 9: Length and width of a field are in the ratio 5 : 3. If the width of the field is 42 m, then its length is

(a) 50 m

(b) 70 m

(c) 80 m

(d) 100 m

ANSWER: (b) 70 m

Ratio of length and width of the field = 5 : 3

Let the length be x m.

∵ Width = 42 m

ANSWER: (a) 95

Consider

Question 12: If 4, a, a, 36 are in proportion, then a =
(a) 24
(b) 12
(c) 3
(d) 24
ANSWER: (b) 12

4, a, a, 36 are in proportion; therefore, we get:

4 : a : : a : 36

Question 13: If 5 : 4 : : 30 : x, then the value of x is
(a) 24
(b) 12
(c) 3/2
(d) 6 
ANSWER: (a) 24
5 : 4 : : 30 : x 

Question 14: If a, b, c, d are in proportion, then

(a) ab = cd

(b) ac = bd

(c) ad = bc

(d) None of these

ANSWER: (c) ad = bc

∵ a, b, c and d are in proportion.

∴ a : b = c : d

⇒a/b = c/d

⇒ ad = bc

Question 15: The weight of 45 folding chairs is 18 kg.How many such chairs can be loaded on a truck having a capacity of carrying 4000 kg load?

ANSWER: Number of folding chairs weighing 18 kg = 45

Number of folding chairs weighing 1 kg = 45/18

Number of folding chairs weighing 4,000 kg