Practice Fractions based ratio and proportion problems - quantitative aptitude Online Quiz (set-1) For All Competitive Exams

Q-1)   Two numbers are in the ratio 1$1/2 : 2 2/3$, when each of these is increased by 15, they are in the ratio 1$2/3 : 2 1/2$ . The greater of the numbers

(a)

(b)

(c)

(d)

Explanation:

First number = ${3x}/2$

and second number = ${8x}/3$

According to the question,

${{3x}/2 + 15}/{{8x}/3 + 15}= {5/3}/{5/2}$

${{3x+ 30}/2}/{{8x + 45}/3} = 5/3 × 2/5 = 2/3$

${(3x + 30)× 3}/{(8x + 45) × 2} = 2/3$

32x + 180 = 27x + 270

32x - 27x = 270 - 180

5x = 90

$x = 90/5$ = 18

Larger number = ${8x}/3$

= ${8 × 18}/3$ = 48


Q-2)   If 177 is divided into 3 parts in the ratio $1/2 : 2/3 : 4/5$, then the second part is

(a)

(b)

(c)

(d)

Explanation:

Ratio of division

= $1/2 : 2/3 : 4/5$

= $1/2 × 30 : 2/3 × 30 : 4/5$ × 30

[LCM of 2, 3 and 5 = 30]

= 15 : 20 : 24

Sum of the terms of ratio

= 15 + 20 + 24 = 59

Second part

= Rs.$(20/59 × 177)$ = Rs.60


Q-3)   If x : y = 3 : 4, then the value of (4x - y) : (2x + 3y) is

(a)

(b)

(c)

(d)

Explanation:

$x/y = 3/4$

${4x - y}/{2x +3y} ={4x/y-1}/{2x/y+3}$

= ${4 × 3/4 - 1}/{2× 3/4+ 3}$

= $2/{3/2+ 3} = {2× 2}/9 = 4 : 9$


Q-4)   If $x/y = 3/4$, the ratio of (2x + 3y) and (3y - 2x) is

(a)

(b)

(c)

(d)

Explanation:

$x/y = 3/4$ (Given)

${2x + 3y}/{3y - 2x} = {2x/y +{3y}/y}/{{3y}/y-{2x}/y}$

(Dividing numerator and denominator by y)

= ${2x/y+3}/{3 - 2 x/y} = {2× 3/4+3}/{3-2× 3/4}$

= ${3/2 + 3}/{3 - 3/2}$

= ${3 + 6}/{6 - 3}= 9/3$ = 3 : 1


Q-5)   Find the fraction which bears the same ratio to $1/27$ that $3/7$ does to $5/9$.

(a)

(b)

(c)

(d)

Explanation:

Let the required fraction be x.

According to the question,

$x : 1/27 = 3/7 : 5/9$

$x × 5/9 = 1/27 × 3/7 = 1/63$

$x = 1/63 × 9/5 = 1/35$


Q-6)   Rs. 782 is divided into three parts in the ratio $1/2 : 2/3 : 3/4$, the first part is

(a)

(b)

(c)

(d)

Explanation:

A : B : C = $1/2 : 2/3 : 3/4$

= $(1/2 ×12) : (2/3 × 12) : (3/4 × 12)$

= 6 : 8 : 9

Sum of the terms of ratio

= 6 + 8 + 9 = 23

First part

= Rs.$(6/23 × 782)$ = Rs.204


Q-7)   A and B together have Rs. 6300. If $5/19$ th of A’s amount is equal to $2/5$ th of B’s amount. The amount of ‘B’ is

(a)

(b)

(c)

(d)

Explanation:

According to the question,

${5A}/19 = {2B}/5$

$5A = {19 × 2B}/5$

A = ${38 × B}/{5× 5}$

A : B = 38 : 25

Sum of the terms of ratio

= 38 + 25 = 63

B’s share = Rs.$(25/63 × 6300)$

= Rs.2500


Q-8)   If x : y = 3 : 4 and y : z = 3 : 4, then ${x + y + z}/{3z}$ is equal to

(a)

(b)

(c)

(d)

Explanation:

x : y = 3 : 4 = 9 : 12

y : z = 3 : 4 = 12 : 16

x : y : z = 9 : 12 : 16

${x + y + z}/{3z} - {9k +12k +16k}/{3 × 16k} = 37/48$


Q-9)   If A : B = $1/2 : 1/3$, B : C = $1/5 : 1/3$, then (A + B) : (B + C) is equal to

(a)

(b)

(c)

(d)

Explanation:

A : B = $1/2 : 1/3$ = 3 : 2

B : C = $1/5 : 1/3$ = 3 : 5

$A/B = 3/2$

${A+B}/B = {3+2}/2 = 5/2$

$B/C = 3 : 5 ⇒ C/B = 5/3$

${C+B}/B = 5/3 + 1 = 8/3$

${A+B}/{C+B} = 5/2 ÷ {8/3}$

= $5/2 × 3/8 = 15/16$ = 15 : 16


Q-10)   The reciprocals of the squares of the numbers 1$1/2$ and 1$1/3$. are in the ratio

(a)

(b)

(c)

(d)

Explanation:

Ratio of the squares of $3/2$ and $4/3$

= $9/4 : 16/9$

Ratio of their reciprocals = $4/9 : 9/16$ = 64 : 81