Friday, September 30, 2016
Question of the day
QUESTION OF THE DAY - 30/09/2016
A bag contains 375 currency notes consisting of 5 rupee, 10 rupee and 50 rupee currencies in the ratio 4 : 8 : 3 respectively. Out of this Rs 50 is spent and the left out money is exchanged for 100 rupee currency notes. Then the number of 100 rupee currency notes is ___
- 62
- 52
- 72
- 68
- 50
A bag contains 375 currency notes consisting of 5 rupee, 10 rupee and 50 rupee currencies in the ratio 4 : 8 : 3 respectively. Out of this Rs 50 is spent and the left out money is exchanged for 100 rupee currency notes. Then the number of 100 rupee currency notes is ___
- 62
- 52
- 72
- 68
- 50
Time & Work ( Part - 5)
Working Alternate Days
So far we have seen problems based on individual work, group work and working in pairs, and asked to find individual work or group work depending on the question. I hope that you people enjoying these posts and updating yourself. In this post iam providing stuff about the concept of people working alternate days.
Working alternate days means.... lets consider A and B are employed in a work and they are working alternate days. That means one day A is working and the other day B is working on the same work. And completes the work.
NOTE: It is important that who is starting the work.
Let's understand this concept by an example:
Q: A and B are employed to finish a work. A alone can complete the work in 10 days while B alone in 15 days. If they work on alternate days, starting with A, find the number of days taken to finish the job?
Sol: Here A is working on 1st day. [A B A B A B A B ... This is the pattern]
A ---- 10 6
60 (Total work)
B ---- 15 4
Day - 1: A does 6 work
Day - 2: B does 4 work
i.e., in 2 days -----> 10 work is done
2*6 days -----> 10*6 = 60 work
thus, 12 days required to complete the work.
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Q: A and B working separately can do a piece of work in 20 and 24 days. They work on alternate days starting with B on the first day. In how many days will the work be completed?
- 23 days
- 22 days
- 21 (5/6) days
- 21 days
Sol: A ---- 20 6
120
B ---- 24 5
B is starting, B A B A B A B A ....
2 days ------ 11 work
2*10 = 20days ------ 11*10 = 110 work
Remaining work = 120 - 110 = 10
21st day B --- 5 work
Remaining work is 10 - 5 = 5
This is done by A in 5/6 days (not a complete day).
Hence, Total days = 21(5/6) days.
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Try this:
Q: A, B and C can do a work in 6, 10 and 8 days respectively, working individually. They started the work doing alternately. Find the number of days required to complete the work, if
(a) A started the work.
(b) B started the work.
(c) C started the work.
Post your answer in comment box below. Solution is provided soon...
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Tuesday, September 27, 2016
Time & Work ( Part - 4)
Persons working in PAIRS
When questions are asked about people working in pairs, and asked to find the combined work and hence individual work also. Lets understand this concept with the help of following example.
Q: A and B can do a work in 12 days, B and C can do it in 15 days and C and A can complete it in 20 days. If A, B and C work together the work will be completed in how many days?
- 5 days
- 47/6 days
- 10 days
- 47/3 days
- None of these
Sol:
A + B ------------- 12 5
B + C ------------- 15 60 4
C + A ------------- 20 3
------------ -------
2(A+B+C) 12
2(A+B+C) --------- 60/12 = 5 days
(A+B+C)--------- 5*2 = 10 days
NOTE: To find individual work,
A - alone:
A+B+C -------- 10 3
30
B+C -------- 15 2
----------- ------
A 1
A = 30/1 = 30 days
B - alone:
A+B+C -------- 10 4
40
C+A -------- 20 2
----------- ------
B 2
B = 40/2 = 20 days
C - alone:
A+B+C -------- 10 6
60
A+B -------- 12 5
----------- ------
C 1
C = 60/1 = 60 days
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In this way we can proceed to unfold the task. Dear viewers... do practise more and more questions of same kind. And leave a comment if you have any doubts.
Question of the day
QUESTION OF THE DAY - 27/09/2016
A person sells a table at a profit of 10%. If he had bought the table at 5% less cost and sold for Rs.80 more, he would have gained 20%. The cost price of the table is
- Rs 3200
- Rs 2500
- Rs 2000
- Rs 3500
- Rs 2200
Saturday, September 24, 2016
Question of the day
QUESTION OF THE DAY - 25/09/2016
The average height of 18 boys in a class is170 cm. If the heights of 15 new boys are added, the new average increase by 3 cm. What is the average height of the 15 new boys?
- 176.6 cm
- 172.3 cm
- 178.4 cm
- 174.6 cm
- None of these
Thursday, September 22, 2016
Question of the day
QUESTION OF THE DAY - 22/09/2016
Two trains start from P and Q respectively and travel towards each other at a speed of 50 kmph and 40 kmph respectively. By the time they meet, the first train has travelled 100 km more than the second. Then the distance between P and Q is ____
- 500 km
- 630 km
- 660 km
- 900 km
- 850 km
Time & Work (Part - 3)
WHEN GROUP WORK IS GIVEN & ASKED TO FIND INDIVIDUAL WORK
In these types of questions the time taken by a group of persons to complete a particular work is given and time taken by one individual also given. Then asked to find the time taken to complete the same work by the other individual.
How to solve these types of questions? Lets see.
As discussed in the previous post, we'll follow the same procedure with a little change.
This concept will be cleared by the following example.
Q: A and B can finish a piece of work in 6 days and A alone can do it in 9 days. The time taken by B alone to do the work is?
(A) 20 days
(B) 18 days
(C) 24 days
(D) 16 days
(E) None of these
Sol: A + B ----- 6 3
18
A ----- 9 2
---------
Diff = 1 (3-2)
Therefore, B ----- 18/1 = 18 days
Hence, B alone can complete the work in 18 days.
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To master this concept do practice more number of similar problems.
Try this:
Q: A and B together can do a piece of work in 8 days. If A alone can do the same work in 12 days, then B alone can do the same work in?
(A) 20 days
(B) 16 days
(C) 24 days
(D) 28 days
(E) None of these
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Q: A can do a piece of work in 4 days. B can do it in 5 days. With the assistance of C they completed the work in 2 days. Find in how many days can C alone do it?
(A) 10 days
(B) 20 days
(C) 4 days
(D) 5 days
(E) None of these
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ALL THE BEST
Wednesday, September 21, 2016
Question of the day
Question of the day - 21/09/2016
The average age of husband and wife was 23 years at the time of their marriage. After 5 years they have a one year old child. The average age of the family now is ____
- 28.5 years
- 19 years
- 29.9 years
- 23 years
- 24 years
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Tuesday, September 20, 2016
Time & Work (Part -2)
When Individual work is given & Asked to find group work
In these types of questions the time taken by two or more persons to complete a particular work (Individual) is given and asked to find the time taken to complete the same work when they are working together (group).
How to solve these types of questions? Lets see.
- Assume the total work (Any number, say 100).
- Divide the total work by individual work (this gives the per day work).
- Add the per day works.
- Divide total work with combined per day work.
- The resultant is the required answer.
NOTE: This method is also known as LCM method.
This concept will be cleared by the following example.
Q: A can do piece of work in 10 days and B can complete the same work in 15 days. If they decided to work together, in how many days the work will be completed?
(A) 5 days
(B) 6 days
(C) 8 days
(D) 11 days
(E) 16 days
Sol: A ----- 10 3
30
B ----- 15 2
--------------
Sum = 5 (3+2)
Here 30 can be assumed as total work and 3 (= 30/10) and 2 (= 30/15) are per day work of A & B respectively.
Combined per day work = 3 + 2 = 5
Required answer = 30 / 5 = 6 days.
Here you can assume any number (60, 90, 120,150 etc) instead of 30 and calculate per day work accordingly.
Initially you may confuse to use this method. Practice a set of similar questions to to build command. This is so simple and easy concept to get the answer quickly.
Observations:
- The combined work cannot be more than the individual work, always. (Here it is 6 less than both 10 and 15).
NOTE: We can extend this concept to any number of persons.
Try this:
Q: A , B and C can complete a work in 10, 12 and 15 days respectively, while working alone. If they are working together, the work will be completed in how many days?
(A) 6 days
(B) 8 days
(C) 4 days
(D) 10 days
(E) None of these
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Take any standard book and start solving questions from this topic. Still you have any doubts post your comment.
Time & Work (Part -1)
Time and work
This is topic deals with the concepts of time and work. This topic contributes at least two questions in BANK exams, RRBs and other competitive exams. Students think that the questions from this topic are hard and tricky. This topic is not so hard as you think. If the concept is clear then the rest of the things becomes so easy.
First of all think how the questions being asked. The possible ways of asking questions from this topic are as follows:
- Finding group work
- Finding individual work
Now, the thing is in how many ways the questions can be framed under this section. The possibilities are:
- Individual work is given
- Group work is given
- Working alternately
- People joining and leaving the work
- Work efficiencies are given
- Miscellaneous Problems
If you break the complete time and work in these way, then your task will become easy i.e. both preparation and scoring.
NOTE: If you are comfortable with Time - Work, then Pipes & Cisterns is complementary.
We will discuss all these concepts one by one in upcoming posts. Stay tuned...
Welcome Post
"Aptitude Tricks"
Dear viewers...
Welcome to my blog "Aptitude Tricks". In this i can provide concepts, tricks and tips in aptitude which will be helpful in competitive exams like SBI / IBPS / RRBs / LIC and many others. Make use of this blog. Thankyou... :)
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