- Aptitude Test Preparation
- Aptitude - Home
- Aptitude - Overview
- Quantitative Aptitude

- Aptitude Useful Resources
- Aptitude - Questions & Answers

- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who

# Chain Rules - Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to **Chain Rules**. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using **Show Answer** button. You can use **Next Quiz** button to check new set of questions in the quiz.

Q 1 - If 21 cows eat as much as 15 buffaloes, how many cows will eat as much as 35 buffaloes?

### Answer : A

### Explanation

15 buffaloes = 21 cows ⇒ 1 buffalo = 21/15 cows = 7/5 cows ⇒35 buffaloes = (35 * 7/5 ) cows = 49 cows.

Q 2 - 3 men or 5 women can finish a piece of work in 12 days. How long will 6 men and 5 women take to finish the work?

### Answer : A

### Explanation

3 men = 5 women ⇒ 6 men =10 women ⇒ (6 men +5 women )= 15 women. Let the required number of days be x. More women , less days (Indirect) 15 : 5 :: 12 : x ⇒ 15x = (5* 12 ) ⇒ x= (5*12)/15 = 4 days

Q 3 - If 12 men or 18 women can do a piece of work in 14 days , how long will 8 men and 16 women take to finish the work?

### Answer : A

### Explanation

12 men = 18 women ⇒ 1 man = 18/12 women ⇒ 8 men = (18/12 * 8) women = 12 women ⇒ (8 men + 16 women ) = 28 women Let the required number of days be x. More women, less days (Indirect) 28: 18:: 14 : x ⇒ 28x = (18*14 ) ⇒ x= (18 *14) / 28 = 9days

Q 4 - 8 men can finish a piece of work in 40 days . If 2 more men join with them , then the work will be completed in?

### Answer : B

### Explanation

Let 10 men finish it in x days. More men, less days (Indirect) 10 : 8 :: 40 : x ⇒ 10x = (8 * 40 ) ⇒ x = (8*40) /10 = 32 days.

Q 5 - In a barrack of soldiers there was stock of food for 190 days for 4000 soldiers.After 30 days , 800 soldiers left the barrack. For how many days shall the left over Food last for the remaining soldiers?

### Answer : B

### Explanation

Remaining food was sufficient for 4000 soldiers for 160 days. Remaining soldiers = ( 4000- 800) = 3200. Let the required number of days be x . Less soldiers, more days (Indirect) 3200 : 4000 :: 160 : x⇒ 3200 x = (4000 * 160 ) ⇒ x = (4000 * 160)/3200 = 200 days.

Q 6 - Four examiners can examine a certain number of answer papers in 10 days by working for 5 hours a day. For how many hours in a day would 2 examiners have to work in order to examine twice the number of answer papers in 20 days?

### Answer : D

### Explanation

Let the number of hours per days be x. More days, less hours per days ( Indirect) Less examiners , more hours per days ( Indirect) More Ans. Books , more hours per days ( direct) Days 20 : 10 Examiners 2 : 4 :: 5 : x Ans. Books 1 : 2 ∴ (20 * 2 * 1 * x) = ( 10 * 4 * 2* 5 ) ⇒ x = 400 / 40 = 10 hrs per days.

Q 7 - Running at the same constant rate , 6 identical machines can produce 2700 bottle per minute . At this rate , how many bottles could 10 such machines produce in 4 minutes?

### Answer : B

### Explanation

Let the required number of bottles be x . More machines, more bottles ( Direct) More time, more bottles ( Direct) Machines 6 : 10 :: 2700 : x Time 1:4 (6 * 1 * x) = 10 * 4 * 2700 ) ⇒ 10 * 4 * 2700 / 6 = 1800 bottles.

Q 8 - If the rent for grazing 40 cows for 20 days in Rs 740, how many cows can graze for 30 days on Rs 222?

### Answer : B

### Explanation

Let the required number of cows be x. Less rent, less cows (Direct) More days, less cows (Indirect) Rent 740 : 222 :: 40 : x Days 30: 20 ∴ ( 740 * 30 * x) = ( 222 * 20 * 40 ) ⇒ x = 222* 20 * 40 / 740 * 30 = 8 cows.

Q 9 - 2 men and 7 boys can do a piece of work in 14 days ; 3 men and 8 boys can do the same in 11 days . 8 men and 6 boys can do 3 times the amount of this work in

### Answer : A

### Explanation

Let 1 men 1 days work be 1/x and 1 boy 1 day work be 1/y Then 2/x + 7/y = 1/14 ⇒ 2u + 7v = 1/14 -(i) When u= 1/x, v=1/y. 3/x +8/y =1/11 ⇒ 3u + 8v = 1/11?.(ii) Multiplying (i) by (ii) by 2 and subtracting , we get: 5v = ( 3/14 ? 2/11) = 5/ 154 ⇒ v = 1/154 Putting v = 1/154 in (i) we get : 2u +7* 1/154 = 1/14 ∴ 2u = (1/14- 1/22)= (11-7/54) = 4/154 = 2/77 ⇒ u=1/77. (8 men +6 boys) 1 days work = (8/77 +6/154 ) = 22/154 = 1/7. ∴ 8men and 6 boys can do it in 7 days. They will do thrice of this work in (3*7) days = 21days.

Q 10 - 20 men complete one third of a piece of work in 20 days. How many more men should be employed to finish the rest of the work in 25 more days?

### Answer : B

### Explanation

Work done = 1/3, Remaining work = (1- 1/3 ) = 2/3 Let the number of additional men be x. More work, more men (Direct) More days , less men (Indirect) Work 1/3 : 2 /3 :: 20 : (20 +x) Days 25:20 1/3 * 25 * ( 20 + x) = 2 /3 * 20 *20 ⇒ (20 +x) = 32 ⇒ x=12. Required number of days = 12.