Sawaal

 Ratios and Proportions Questions

Popular Latest Rated Important Formulae

FACTS  AND  FORMULAE  FOR  RATIO  AND  PROPORTION  QUESTIONS

 

 

1. RATIO: The ratio of two quantities a and b in the same units, is the fraction a/b and we write it as a:b.

In the ratio a:b, we call a as the first term or antecedent and b, the second term or consequent.

Ex. The ratio 5: 9 represents 5/9 with antecedent = 5, consequent = 9.

Rule: The multiplication or division of each term of a ratio by the same non-zero number does not affect the ratio. Ex. 4: 5 = 8: 10 = 12: 15 etc. Also, 4: 6 = 2: 3.

 

2. PROPORTION : The equality of two ratios is called proportion. 

If a: b = c: d, we write, a: b :: c : d and we say that a, b, c, d are in proportion . Here a and d are called extremes, while b and c are called mean terms.

Product of means = Product of extremes.

Thus, a: b :: c : d <=> (b x c) = (a x d).

 

 3. (i) Fourth Proportional : If a : b = c: d, then d is called the fourth proportional to a, b, c.

     (ii) Third Proportional : If a: b = b: c, then c is called the third proportional to a and b.

     (iii) Mean Proportional : Mean proportional between a and b is ab

 

 4. (i) COMPARISON OF RATIOS : We say that (a: b) > (c: d) ⇔ (a/b)>(c /d).

     (ii) COMPOUNDED RATIO : The compounded ratio of the ratios (a: b), (c: d), (e : f)  is    (ace: bdf)

 

5. (i) Duplicate ratio of (a : b) is a2:b2.

    (ii) Sub-duplicate ratio of (a : b) is (√a : √b).

    (iii)Triplicate ratio of (a : b) is a3:b3.

    (iv) Sub-triplicate ratio of (a : b) is a13: b13.

    (V) If ab=cd, thena+ba-b=c+dc-d (Componendo and dividendo)

 

 6. VARIATION:

(i) We say that x is directly proportional to y, if x = ky for some constant k and we write, x∝y

(ii) We say that x is inversely proportional to y, if xy = k for some constant k and we write, x∝1y

Q:

At a casino in mumbai, there are three tables A, B and C. The payoffs at A is 10:1, at B is 20:1 and at C is 30:1. If a man bets Rs 200 at each table and win at two of the tables, what is the maximum and minimum difference between his earnings can be?

A) Rs.2500 B) Rs.2000
C) Rs.4000 D) None of these
 
Answer & Explanation Answer: C) Rs.4000

Explanation:

Maximum earning will be only when he will won on the maximum yielding table.

     A ----> 10:1

     B ----> 20:1

     C ----> 30:1

 i.e, he won on B and C but lost on A

 20 x 200 + 30 x 200 -1 x 200 = 9800

 minimum earning will be when he won on  table A and B and lose on that table 3.

 

Therefore, 10 x 200 + 20 x 200 - 1 x 200  =  6000-200 = 5800

Therefore, Difference= 9800 - 5800 = 4000

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions

12 7631
Q:

If two complimentary angles are in the ratio of 4 : 5, find the greater angle.

 

A) 40 deg B) 50 deg
C) 60 deg D) 30 deg
 
Answer & Explanation Answer: B) 50 deg

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions
Exam Prep: Bank Exams

1 7628
Q:

6 pumps of kirlosker can fill a tank in 7 days and 2 similar pumps of USHA can fill the same tank in 18 days. what is the ratio of the efficiency of a kirlosker pump and a USHA pump?

A) 6:7 B) 7:6
C) 7:54 D) None of these
 
Answer & Explanation Answer: A) 6:7

Explanation:

The number of days required by a single kirlosker pump to fill the tank = 6 x 7 =42 days and the number of days required by a single USHA pump to fill the same tank = 2 x 18 =36 days.

Now , since efficiency is inversely proportional to the number of days. Hence,

Efficiency of one K - pumpEfficiency of U- pump=3642=67  

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions

7 7472
Q:

Out of 135 applicants for a post, 60 are graduates and 80 have experience. What is the ratio of minimum to maximum number
of graduates having experience?

A) 12:1 B) 5:1
C) 1:5 D) 1:12
 
Answer & Explanation Answer: D) 1:12

Explanation:

Given total applicants = 135
Given graduates are G=60
Otherthan graduates=135-60 = 75
Given experienced candidates = 80
1) For maximum number of graduates have experience
    Total graduates to have experience = 60

2) For minimum number of graduates have experience
    Remaining after taking other than graduates in experience= 80-75 = 5

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions
Exam Prep: Bank Exams , CAT
Job Role: Bank Clerk , Bank PO

13 7447
Q:

A company requires 12,100 strength. Present employees are 400 ladies and 6400 gents. To reach the target how many ladies required to maintain the same ratio ?

A) 400 B) 600
C) 900 D) 700
 
Answer & Explanation Answer: C) 900

Explanation:

6,400 gents, 2400 ladies in that company.
So total 8,800employees.
for 8,800 employees, we want 2400 ladies.
for 12,100employees we want how many ladies ?
=> (12,100/8,800) x 2400 = 3300.
So we want 3300 - 2400 = 900 more ladies.

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions
Exam Prep: AIEEE , Bank Exams , CAT , GATE , GRE
Job Role: Bank Clerk , Bank PO

11 7293
Q:

Find the missing value denoted by '?'

 

3 : 243 :: 5 : ?

 

A) 625 B) 465
C) 3125 D) 425
 
Answer & Explanation Answer: C) 3125

Explanation:
Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions
Exam Prep: Bank Exams

5 6976
Q:

In a cricket match total number of runs scored by Virat, Dhoni and Rohit is 285. The ratio of the number of runs scored by Virat and Rohit is 3 : 2 and that of the runs scored by Rohit and Dhoni is also 3 : 2. The number of runs scored by Virat in that match?

A) 154 B) 135
C) 112 D) 106
 
Answer & Explanation Answer: B) 135

Explanation:

From the given data,

Virat : Rohit = 3 : 2

Rohit : Dhoni = 3 : 2

Ratio of runs scored by Virat, Rohit and Dhoni respectively

= 3 x 3 : 2 x 3 : 2 x 2

9 : 6 : 4

Runs scored by Virat = 9/19 x 285 = 135.

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions
Exam Prep: AIEEE , Bank Exams , CAT
Job Role: Analyst , Bank Clerk , Bank PO

26 6774
Q:

A Product is supported each week by the same three Product supporters. Last month the first supporter took 440 calls, the second took 360 calls, and the third took 300 calls. This month the job will consists of 1500 calls. If the three supporters each increase their work proportionately, how many more calls will the second supporter take this month than last month ?

A) 131 calls B) 160 calls
C) 491 calls D) 600 calls
 
Answer & Explanation Answer: A) 131 calls

Explanation:

1st supporter recieve 440 calls
2nd supporter recieve 360 calls
3rd supporter recieve 300 calls

So total calls = 1100 calls ;
Calls this month= 1500
So remaining calls to be distributed is 400

So Now Ratio 1st:2nd:3rd ==> 440:360:300
=> 22:18:15

Now No. of More Calls 2nd supporter will get => [18/(22+18+15)] x 400
=> (18/55) x 400
=> 131 Calls
So 131 more Calls than last month.

Report Error

View Answer Report Error Discuss

Filed Under: Ratios and Proportions
Exam Prep: AIEEE , Bank Exams , CAT , GATE , GRE
Job Role: Analyst , Bank Clerk , Bank PO

7 6493