Ratio and Proportion - Aptitude Questions and Answers

Ratio and Proportion Questions and Answers

Learn and practice the chapter "Ratio and Proportion" with these solved Aptitude Questions and Answers. Each question in the topic is accompanied by a clear and easy explanation, diagrams, formulae, shortcuts and tricks that help in understanding the concept.

Use of Ratio and Proportion Questions

The questions and examples given in this section will be useful to all the freshers, college students and engineering students preparing for placement tests or any competitive exam like MBA, CAT, MAT, SNAP, MHCET, XAT, NMAT, GATE, Bank exams - IBPS, SBI, RBI, RRB, SSB, SSC, UPSC etc.

Practice with this online test to crack your placements and entrance tests!
1. Which of the following two ratios is greater?

15and9
1311

a.15
13
b.9
11
c. Both are same
d. Cannot determine

Answer: a.15
13

Explanation:

It is easier to compare the fractions if they have common denominators.
Let's try to do that:
We have 13 and 11 in the denominator.
So, multiply first fraction up and down with 11 as shown
15 x 11=165------------------> 1st
13 x 11143
Multiply second fraction up and down with 13 as shown
9 x 13=117--------------------> 2nd
11 x 13143
Numerator of 1st is greater (165 > 117); so 15:13 is greater than 9:11

Tip:
- If numerator of 1st was smaller, when denominators were same, then 1st fraction would have been smaller than 2nd.


2. Find the 3rd proportional to 9 and 72.

a. 8
b. 216
c. 576
d. 648

Answer: c. 576

Explanation:

In a:b:c, 3rd proportional is c.
a:b:c can be written as a:b::b:c

a:b::b:c can be written asa=b   =>   b2 = ac
bc
Here, a:b:c = 9:72:c
∴ 72 x 72 = 9 x c
∴ c =72 x 72= 576
9





3. Find the 4th proportional in 7, 23 and 217?

a. 66
b. 506
c. 713
d. 961

Answer: c. 713

Explanation:

In a:b::c:d , 4th proportional is d.

a:b::c:d can be written asa=c=> d =c x b
bda
Here, a:b::c:d = 7:23::217:d
∴ d =23 x 217= 713
7


4. Find the mean proportional between 9 and 81?

a. 21
b. 27
c. 35
d. 729

Answer: b. 27

Explanation:

In a:b:c, mean proportional = b
a:b:c can be written as a:b::b:c

a:b::b:c =>a=b=>  b2 = ac => b = ac
bc
Here, a = 9; c = 81
∴ b = 9 x 81 = 27


5. Rajesh and Somesh were classmates. Their earnings now are in the ratio 5:6. The ratio of their expenses is 7:9. Somesh saves Rs 3,000 every month while Rajesh saves Rs 1000/- more than Somesh. Find the total earnings and expenses of each of them.  

a. Rajesh - 25000, 21000; Somesh - 30000, 27000
b. Rajesh - 30000, 27000; Somesh - 36000, 32000
c. Rajesh - 36000, 32000; Somesh - 30000, 27000
d. None of the above

Answer: a. Rajesh - 25000, 21000; Somesh - 30000, 27000

Explanation:

Income ratio = Rajesh : Somesh = 5:6 =5;
6
Common factor helps in finding actual values easily
So, take 'A' as common factor.
Income of Rajesh = 5A; Income of Somesh = 6A
Expenses of Rajesh=Rajesh Income - Rajesh Saving=7
Expenses of SomeshSomesh Income -Somesh Saving9
Since Rajesh save, Rs 1000/- more than Somesh, Rajesh's savings = Rs 4000/-
5A-4000=7
6A-30009
∴ 9(5A-4000) = 7(6A-3000)
∴ A = 5000
Income of Rajesh = 5A = 25000 ; Income of Somesh = 6A = 30000
Spending of Rajesh =25000 - 4000 = 21000
Spending of Somesh = 30000 - 3000 = 27000