**Please read**

**Part-1**

**, before going through this post. In this article, I have solved questions where some workers quit in the middle, as well as some questions on efficiencies.**

**In the complete Time and Work series, Efficiency would mean "Work Done in 1 day", and efficiency has been denoted by small letters, e.g. "a" means "Efficiency of A".**

__Note:__

If Pratibha finishes the work in X days, then Sonia will take 3X days to finish the same work

Given 3X – X = 60

Or X = 30

Pratibha takes 30 days and Sonia takes 90 days

**Answer: (A)**

Let the total work be 24 units.

Efficiency of Sunil = 24/4 = 6 units (Since Sunil takes 4 days to complete the work)

Efficiency of Ramesh = 6 * 1.5 = 9 units (Since Ramesh is 1.5 times efficient as Sunil)

Efficiency of Dinesh = 24/6 = 4 units ((Since Sunil takes 6 days to complete the work))

Efficiency of (Sunil + Ramesh + Dinesh) = 6 + 9 + 4 = 19 units

Time required to finish the complete work = 24/19 days

Let the total work be 15 units. Efficiency of A = a and Efficiency of B = b

A and B complete the work in 5 days.

Hence efficiency of A and B = 15/5 = 3 units

So, a + b = 3 … (1)

New efficiency of A = 2a

New efficiency of B = b/3

With new efficiency the work was completed in 3 days.

So, 2a + b/3 = 15/3 = 5 … (2)

Solve (1) and (2), you will get a = 12/5 = 2.4 units

So A will complete 15 units work in 15/2.4 or 25/4 days

Let the total work be 24 units

Given, 3*Efficiency of A = Efficiency of B + Efficiency of C

3a = b + c

A, B and C compete the work in 24 days.

Hence, a + b + c = 24/24 = 1 or 4a = 1 [Put b + c = 3a]

a = 1/4 = 0.25 unit

A completes 0.25 unit work in 1 day. So to complete 24 units of work, he will take 24/0.25 = 96 days

Let the total work be 7 units. Since they all complete the work in 7 days, so their total efficiency = 7/7 = 1 unit

Let efficiency of boy = x

Then efficiency of women = 2x

Efficiency of man = 4x

x + 2x + 4x = 1

7x = 1 or x = 1/7

The boy completes 1/7 work in 1 day, so to complete 7 units of work, he will take 49 days

A does 1/2 as much work as B in 3/4 of the time. Hence A will do (1/2 + 1/2) or complete work in (3/4 + 3/4) or 1.5 times more time than B.

A = 1.5B (where A = no. of days taken by A to finish the work and B = no. of days taken by B to finish the work)

Also A*B/(A+B) = 18

Put A = 1.5B in the above equation and solve

B = 30 days

Time required to finish the complete work = 24/19 days

**Answer: (D)**A and B complete the work in 5 days.

Hence efficiency of A and B = 15/5 = 3 units

So, a + b = 3 … (1)

New efficiency of A = 2a

New efficiency of B = b/3

With new efficiency the work was completed in 3 days.

So, 2a + b/3 = 15/3 = 5 … (2)

Solve (1) and (2), you will get a = 12/5 = 2.4 units

So A will complete 15 units work in 15/2.4 or 25/4 days

**Answer: (B)**Given, 3*Efficiency of A = Efficiency of B + Efficiency of C

3a = b + c

A, B and C compete the work in 24 days.

Hence, a + b + c = 24/24 = 1 or 4a = 1 [Put b + c = 3a]

a = 1/4 = 0.25 unit

A completes 0.25 unit work in 1 day. So to complete 24 units of work, he will take 24/0.25 = 96 days

**Answer: (B)**Let the total work be 7 units. Since they all complete the work in 7 days, so their total efficiency = 7/7 = 1 unit

Let efficiency of boy = x

Then efficiency of women = 2x

Efficiency of man = 4x

x + 2x + 4x = 1

7x = 1 or x = 1/7

The boy completes 1/7 work in 1 day, so to complete 7 units of work, he will take 49 days

**Answer: (A)**A = 1.5B (where A = no. of days taken by A to finish the work and B = no. of days taken by B to finish the work)

Also A*B/(A+B) = 18

Put A = 1.5B in the above equation and solve

B = 30 days

**Answer: (B)**

Let the total work = 60 units

Efficiency of A = 60/20 = 3 units

Efficiency of B = 60/30 = 2 units

Efficiency of (A + B) = 5 units

Work done by A and B in 7 days = 5*7 = 35 units

Work left = 60 – 35 = 25 units

C completes 25 units of work in 10 days. Hence he will complete 60 units of work in 10* 60/25 = 24 days

**Answer: (C)**

Let total work be 120 units.

Efficiency of A = 120/6 = 20 units

Efficiency of B = 120/12 = 10 units

Efficiency of C = 120/15 = 8 units

Work left = 7/8 * 120 = 105 units

Efficiency of A + B = 30 units

Hence time taken by A and B to complete 105 units of work = 105/30 = 3.5

**Answer: (C)**

Let the total work = 80 units

Efficiency of (A + B + C) = 80/40 = 2 units

Work done by (A + B + C) in 16 days = 16 * 2 = 32 units

Remaining work = 80 – 32 = 48 units

B and C complete the remaining work (48 units) in 40 days.

Efficiency of B + C = 48/40 = 1.2 units

Efficiency of A = Efficiency of (A + B + C) - Efficiency of (B + C) = 2 – 1.2 = 0.8 unit

Time taken by A to complete the whole work = 80/0.8 = 100 days

**Answer: (C)**

Let the total work = 360 units

Efficiency of A = 360/45 = 8 units

Efficiency of B = 360/40 = 9 units

Efficiency of A + B = 17 units

Let A left after x days, that means A and B worked together for x days. Total work done by A and B together = 17x

Then the remaining work is finished by B in 23 days. Hence work done by B alone = 23 * 9 = 207 units

So, 17x + 207 = 360

Or x = 9 days

**Answer: (D)**

This question appeared in SSC Tier-2 2015, and stumped many candidates. Although there is nothing tricky about it.

Let the total work be 60 units.

p + q = 60/6 = 10

q + r = 60*7/60 = 7

Given, Total work done = 3 days work of P + 6 days work of Q and R

60 = 3*p + 6*(7)

p = 6

Hence time taken by P to complete the work = 60/6 = 10 days

p + q = 10, hence q = 4

q + r = 7, hence r = 3

Hence time taken by R to complete the work = 60/3 = 20 days

Difference = 20 - 10 = 10 days

**Answer : (C)**

**Q. 12) 4 Men and 6 Women working together can complete the work in 10 days. 3 men and 7 women working together will complete the same work in 8 days. In how many days 10 women will complete this work?**

**One day work for a man = 1/m**

One day work for a woman = 1/w

In one day, 4 men and 6 women will do 1/10 of the work. Hence,

4/m + 6/w = 1/10 ... (i)

4/m + 6/w = 1/10 ... (i)

Similarly,

3/m + 7/w = 1/8 ... (ii)

Multiply equation (i) with 3 and equation (ii) with 4

12/m + 18/w = 3/10

12/m + 28/w = 1/2

Subtract the equations

10/w = 1/5

So 10 women will complete the work in 5 days

3/m + 7/w = 1/8 ... (ii)

Multiply equation (i) with 3 and equation (ii) with 4

12/m + 18/w = 3/10

12/m + 28/w = 1/2

Subtract the equations

10/w = 1/5

So 10 women will complete the work in 5 days

**Answer: (5)**

**If you have any doubt in this article, please drop a comment...****Keep reading :)**

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thanks sir

ReplyDeletethanks sir

ReplyDeleteSir

ReplyDeleteAaj ke AMAR UJALA me nikla h ki ssc ka pre qualifyinh hoga aur mains online hoga aur usipe merit bnegi.

Aapki kya report h?

iss saal koi change nai hoga, so don't worry

Deletehttp://m.dailyhunt.in/news/india/hindi/amar-ujala-epaper-amar/sijiel2016-ka-pariksha-paitarn-badala-newsid-52031476

ReplyDeleteSir, What should be my strategy in these last 20 days to maximize my score in tier-1? It is a common question. Please write a post if possible.

ReplyDeleteSir pls tell by efficiency method:-

ReplyDeleteTwo pipes can fill a cistern separately in 24 min and 40 min respectively. A waste pipe can drain off 30 litres per minute. If all the three pipes are opened the cistern fills in one hour. The capacity of Cistern is?

Capacity is 720 ltrs...?

DeleteYou wont be able to solve this question with efficiency method because waste pipe ki efficiency absolute terms me di hai (30 litres).

DeleteLet the capacity be X

In 1 minute, the first pipe adds X/24 litres

In 1 minute, the second pipe adds X/40 litres

In 1 minute, the third pipe drains off 30 litres

So in 1 minute, all the three pipes are adding (X/24 + X/40 - 30) litres.In 60 minutes, all the three pipes will add 60*(X/24 + X/40 - 30) litres. Hence

X = 60*(X/24 + X/40 - 30)

X = 600 litres

i don't know what is efficiency method but a simple way to solve it is- since all the pipes are opened for 60 min

Delete(1 hr) that means 60/24 + 60/40 -60/C = 1

solving it will give c=20. if C operates for 20 min then it'll fill 20*30 = 600 litres [C empties 30 litres per min)

I am yamuna new to ssc exam. Iam preparing last year papers and some shortcuts from your blog.

ReplyDeleteIs it enough to pass in tier-1?

Please tell me the strategy that I have to follow for these 20 days?

No answer is 600 waiting for sir to reply

ReplyDeleteThis comment has been removed by the author.

ReplyDeleteIn ques 7 sir, we considered 20 and 30 only for lcm right? Because the othef two members are leaving and joining in btwn?

ReplyDeleteyes...jiska jiska complete work diya ho, usi ka LCM nikalna hai

DeleteIn ques 7 sir, we considered 20 and 30 only for lcm right? Because the othef two numbers are about leaving and joining in btwn?

ReplyDeleteCool! Thanks sir :-)

ReplyDeleteSir pls explain q.no 6 in detail.why take 3/4+3/4 I can't understand

ReplyDeleteHello Sir,

ReplyDeleteQ.9...total work 80 units..how??...it is just an assumption or any logic behind it?

Looking forward for your reply:)

LCM of 40 and 16

DeleteOops..yeah..got it...thank you so much for the response:)

Deletewhy you have taken 42 units in last question...? Any logic behind this?

ReplyDeleteNo logic...take whatever you want...

DeleteSir plzz post some more tricks for trignometry & algebra using option

ReplyDeletesir Q.6 me i think answer is 45

ReplyDeletebecause 3/4B = 1/2A diya hai

to A=1.5B aayega

aur A+B=1 hai to A ki value put karne ke baad

B=1/1.5 aa raha hai to B=45 aayega na?

please explain

nai yar...b=30 hi aayega...farzi me confuse kar diya tumne :D

DeleteArey bhai..... A+B=1

DeleteThen A=1.5B

Put the value 1.5B+B=1

2.5B=1

B=1/2.5

r u sure answer is 30 :D please explain

Deleteif not then please update the answer

agar main sure na hota to ye question post hi nai karta...how come you are getting A + B = 1

DeleteI mean logic kya hai iss equation ka??

Moreover, B ki efficiency A ki efficiency se jyada hai. So ye obvious hai ki B will take less time than A

Sir! How many questions are generally asked in Tier-I Work ?

ReplyDeleteAround 4

DeleteSir can u explain about question 6… how do u get complete work as 3/4+3/4

ReplyDelete3/4 + 3/4 is not the complete work

DeleteLet B perform W amount of work in T time. Then A will perform W/2 work in 3/4T time. So to perform W work, A will need 3/4T + 3/4T or 1.5T time. Hence,

A = 1.5B

Sir...in q.4...how did u comprehend 3a=b+c??

ReplyDeleteA takes three times as long as B and C together to complete the work. That means the efficiency of A is three times less than B and C together

Deletea = (b + c)/3

3a = b + c

One more thing sir...a lot of cumbersome chit-chats are prevailing out there abt cgl pattern change n ol....it sucks our concentration immensely...plss provide some lucid explanation on that..so that we can replenish our concentration...pls sir..all messed up!!huh

ReplyDeleteIn q.6...where is given 3/4th time more than B...den lastly,how can it be said 1.5times more than B??

ReplyDelete3/4th more time is for 1/2 work. For complete work, the time will be 3/4+3/4 or 1.5 times more

DeleteSir in q.8..whether it is asked to calculate total time taken or time taken for the work remaining...is not clear...should it be decided on the basis of options given??

ReplyDeleteYes...it is not clear...will have to go according to the options only

Delete4 Men and 6 Women working together can

ReplyDeletecomplete the work in 10 days. 3 men and 7

women working together will complete the

same work in 8 days. In how many days 10

women will complete this work?

(A) 8 (B) 7

(C) 5 (D) 4

Please solve this.

4/m + 6/w = 1/10

Delete3/m + 7/w = 1/8

multiply equation (i) with 3 and equation (ii) with 4

12/m + 18/w = 3/10

12/m + 28/w = 1/2

subtract the equations

10/w = 1/5

So 10 women will complete the work in 5 days

Sir even I got this answer but I used below method

Delete(4M+6W) *10 = (3M+7W)*8

40M+60W = 24M +56W

16M = -4W

-1W = 4M

M/W = -1/4

Total work = 200

10 women will complete in 200/40 = 5 days.

In this case men's efficiency comes -1. So is the question wrong? Because if they have asked like this "In how many days 10 men will complete this work?", then what should be the approach.

yes...no of days for men will come negative. Thats why they have asked about women it seems...\your approach is fine, so you shudn't worry about it.

DeleteThank you very much. :)

Deletesir, i use this method to solve but i am not getting the ans

ReplyDelete10(4M +6W) = 8(3M + 7W). Please help.

Eff of 4M + 3W = 80/10 & eff of 3M +7W= 80/8 , now solve both eq. Eff. Of 10W =16 so they will work in 80/16 =5 days .. Ryt sir ?

ReplyDeleteSir,

ReplyDeleteI have a doubt on your post [Q] Time and Work Tricks - 2 on question 2 that,

Suppose I take work as 12 unit s as lcm of 4 & 6 then answer comes as option 1 but you have taken 24 unit work and your ans is D.

So, can u explain which one is right and which concept to follows?

Thanks,

Pawan

SOLUTION PLS -

ReplyDeleteA and B together can finish a work in 15 days . A and C take 2 days more to complete the same work than that of B and C. B and C complete the work in 8 days . In how many days will A finish it separately ?

options - 1) 40 d 2)24d 3) 20 4)17+1/7

Bhai 48 days is the right answer. Not there in the option. Either check ur option or question

ReplyDeleteBhai 48 days is the right answer. Not there in the option. Either check ur option or question

ReplyDelete