In this question, A left after working for 2 days together with B. this question is slightly different from those questions in which A left P days before completion of work(y(x+n)/(x+y))…also this is not that question in which we can only apply (xy/x+y) because it is for determining in how much time both of them will complete the work. so please read the statement and formulas carefully. there is slight difference in all of these 3 types of questions….
This type of Time and Work question is asked in all types of exams whether its competitive or entrance or qualifying and mostly asked in General aptitude or Quantitative Aptitude section of competitive Exams Here is that question’s example:Q: A can do a piece of work in 12 days and B can do the same piece of work in 18 days. Both of them worked together for two days. After 2 days, A left the work. So B has to complete the remaining work by himself. So how long will B take to complete the remaining work?We are sharing with you a very interesting fastmath shortcut trick of a question that is asked mostly in all types of examinations. It is one of the most important question of time and work problem.
We are giving this most important question’s shortcut trick. The trick is so simple that you have to just put the derived formula in to the statement of the questions and you will get the answer straight away.
You have seen this question in most of the exams and used to do it in various steps that takes a normal time of about 2-3 minutes minimum if you can solve faster.
But with this trick or we can say a derived formula shortcut trick you will be able to solve this type of questions in just 10 seconds.
Solution to the above problem:
Now in this type of question, what we normally do is to calculate the two days work of A and B. then we deduct that work from total work and then as per B capability of doing work, we determine how much time he will take to complete that remaining work.
But wait, why are you wasting so much time to do this much calculation when we are giving you the shortcut trick (the derived formula shortcut trick which you will not be able to find in any book or anywhere else).
But you will find this type of derived formulas only
So here is the shortcut solution of the above given problem.
First we need to understand the rule of this type of problems.
Rule
A can do a piece of work in x days and B can do the same piece of work in y days. Both of them worked together for P days. After P days, A left the work. So how long will B take to complete the remaining work?
Solution:
Shortcut Derived Formula Trick:
The remaining work will be completed by B in
y-[P(x+y)/x] days
now let us solve the given question above using this derived formula.
In the question,
Given x=12 days , y= 18 days, P= 2 days
So the remaining work will be completed by B in
y-[P(x+y)/x] = 18-[2(12+18)/12]
= 18-[60/12]
= 13 days
So B will complete the remaining work in 13 days.
What a shortcut derived formula. It hardly takes 10 seconds to solve this type of question using this formula. Is not it.
So how you like the formulas and this site, please give your comments about it. And hit like and share it so that everybody came to know this shortcut trick. Thanks