Machine M can produce x units in 3 / 4 of the time it takes machine N two produce x units. Machine N can produce x units in 2 / 3 the time it takes machine O two produce x units. If all three machines are working simultaneously, what fraction of the total output is produced by machine N?
(A) 1 / 2
(B) 1 / 3
(C) 4 / 13
(D) 8 / 29
(E) 6 / 33
B
B
My answer would be C. 4/13…. could anybody plz explain why they think B is right ?
(C) 4/13
Sorry i stand corrected it is 4/13. I made a silly mistake.
b
B
M N O
x units t/2 2t/3 t
t time 2x 3x/2 x
So for N = 3x/2 / 2x+3x/2+x
3/2 / 9/2 = 1 / 3
M does 2x Job in time T
N does 3X/2 Jobe in time T
O does X job in time T
Total job done working together= 9X/2
therefore N does (3x/2)/9X/2= 1/3 —thus B
C is the answer.
I go with B and ppl have given the explanation. Can the “C” believers give an explanation?
B all the way
let O take 12 hrs to make 1200 units..
then N will take 8 hrs for the same
M will 6 hrs for the same.
If all of them combine- they will finish in 8/3 hrs..
In this 8/3 hrs, the N guy wud make
8/3 * 1200/8 = 400 units.
Thus, total contribution – 1/3
Option B..
Cheers
“And so the fat lady sings.”
b
B
Ans B
Let O produce x in 1 min then N produce x in 2/3 min and M produce x in 1/2 min.
It follows in 1 min,
O produce x
N produce 3/2x
M produce 2x
If they work together fir 1 minute they would produce = 9/2 X.
finally, Fraction of N = 2/3x = 1/3
——-
9/2x
Ans is B (1/3)
What is the question really asking? The trick is the following:
Option A: you are being asked “the fraction of the total output”?
Vs.
Option B: you are being asked “the fraction of the total time it takes them”? (those that choose “C”).
The question is asking “the fraction of the total output”, thus you have to calculate the output of each one, add them up & calculate “the fraction of the total output”.
Official Answer is B.
thanx for the official answer.
I corrected myself
B
B…