Time and Work Problems - Shortcut Tricks and Formulas
Time and Work Problems - Shortcut Tricks and Formulas
Problems Type 1:
A can finish work in X days.
B can finish work in Y days.
Both can finish in Z days = (X*Y) / (X+Y).
Problems Type 2:
Both A and B together can do work in T days.
A can do this work in X days.
then, B can do it in Y days = (X*T) / (X-T)
Problems Type 3:
A can finish work in X days.
B can finish work in Y days.
C can finish work in Z days.
Together they can do work in T days = (X*Y*Z)/ [(X*Y)+(Y*Z)+(X*Z)]
Problems Type 4:
A can finish work in X days.
B can finish work in Y days.
A*X = B*Y
Y = (A*X) / B
Problems Type 5:
A can finish work in X days.
B can finish work in Y days.
A left work after P days then B need to work Q days
Q = [(X - P) / X ] * Y
Problems Type 6:
M1 person can do W1 work in D1 days and H1 hours
M2 person can do W2 work in D2 days and H2 hours
M1D1H1 = M2D2H2
Shortcut tricks on boats and streams are one of the most important topics in exams. These are the formulas and examples on Boats and Streams (Cyclist and the wind or Swimmer and stream) questions. These examples will help you to better understand shortcut tricks on boats and streams questions.
There are multiple types of questions asked from these topics. The speed of the boat in still water and the speed of stream will give in questions, You have to find the time taken by boat to go upstream and downstream. .
The speed of the boat in up and down stream will give in question, you need to find the average speed of the boat.
The speed of boat to go up or down the stream will give in question, you need to find speed of boat in still water and speed of stream.
The time taken by boat to reach a place in up and downstream will given in question, you need to find the distance to the place.
LINE_F...
Permutation and combination related questions are common in PSC and Bank exams.
Before going to Combinations and Permutations, first lean about factorial. .
If n is a positive integer then, factorial of n is denoted as n! . .
4! = (1 x 2 x 3 x 4 ) = 24.
Permutations are for lists of items, whose order matters and combinations are for group of items where order doesn’t matter. in other words, .
When the order of items doesn\\\'t matter, it is called as Combination.
When the order of items does matter it is called as Permutation.
The number of permutations of n objects taken r at a time is determined by using this formula:.
C(n,r)=n!/((n−r)!r!) .
Combination : Picking a team of 3 people from a football coaching group of 10. C(10,3) = 10!(3!(10−3)!) = 120. ....
Code: ABC FIR GJ.
A : America .
B : Britain.
C : Canada.
F : France.
I : Italy.
R : Russia.
G : Germany.
J : Japan.
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