Aptitude - Simplification - Discussion
Discussion Forum : Simplification - General Questions (Q.No. 2)
2.
There are two examinations rooms A and B. If 10 students are sent from A to B, then the number of students in each room is the same. If 20 candidates are sent from B to A, then the number of students in A is double the number of students in B. The number of students in room A is:
Answer: Option
Explanation:
Let the number of students in rooms A and B be x and y respectively.
Then, x - 10 = y + 10 
x - y = 20 .... (i)
and x + 20 = 2(y - 20) x - 2y = -60 .... (ii)
Solving (i) and (ii) we get: x = 100 , y = 80.
The required answer A = 100.
Discussion:
78 comments Page 2 of 8.
Sylvester said:
6 years ago
If 2A=B, Also A=2B.
A=80, B=40, in other words: A=40*2=80.
A=80, B=40, in other words: A=40*2=80.
(5)
Alpesh Patel said:
6 years ago
x-y=20
x=20+y ---> (1)
x-2y=-60 ---> (2)
20+y-2y=-60 --->(3)
+y-2y=-60-20
-y=-80
y=80
Sub value of y in eqn 1, we get;
x=20+80 = 100.
x=20+y ---> (1)
x-2y=-60 ---> (2)
20+y-2y=-60 --->(3)
+y-2y=-60-20
-y=-80
y=80
Sub value of y in eqn 1, we get;
x=20+80 = 100.
(11)
Pratham said:
6 years ago
Hello, can you please explain the last step i.e x=100 y=80?
(3)
Suresh said:
6 years ago
In step 1 how you got 100?
(1)
Hello said:
7 years ago
Where is Ramesh? The one who explained the previous question very simply in this same chapter.
(1)
Swathi hj said:
7 years ago
Why we take x-10 and y+10, can anyone tell me?
(1)
Prakash said:
7 years ago
Could you please explain this? I am not getting it.
Prakash said:
7 years ago
Could you please explain this? I am not getting it.
Sagar said:
7 years ago
Thanks @Naga invy.
Geetha said:
7 years ago
Please Explain the 2nd step.
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