official quant thread for cat08

[vivs_d]

yes the no. of trips will be infinite and there is a theoritical proof for it. i read it wen i was preparing for iit, but have forgotten now.
here the distance to be travelled by bird will keep getting less and will approach to zero, but will never become zero, so the trip will be infinite theoretically.

[r_abhinav]

Originally Posted by hellion

No of males -> m No of females->f

m = 2(f-15)
f = 5(m-45)
m = 2[5m-240]
m = 53.333

Don't know where i have gone wrong

Nothing wrong in ur approach hellion..just a small pit which u overlooked
We will solve step by step

No of Males --> m
No of females --> f

m=2(f-15)

now the second statement is continuation of this statement..so,
(f-15)=2(m-45)

on Solving u get,
m=50
f=40

hope u r clear...
cheers!!!

[hellion]

Originally Posted by hellion

No of males -> m No of females->f

m = 2(f-15)
f = 5(m-45)
m = 2[5m-240]
m = 53.333

Don't know where i have gone wrong

Originally Posted by Hi2All

Friend..
U hav gone wrong in ur first statement itself..

Let No of males=>m No of females=>f

If 15 females are absent,remaining females=f-15
So,according to the question...

f-15=2m (This is the place where u mis understood the question..)
f-2m=15----(1)

If 45 males are absent,then remaining males are=m-45
f=5(m-45)
f-5m=-225---(2)

Subtracting (1)-(2)
3m=240
m=80

f-2m=15
f-160=15
f=175


Rgds
Sidh...

Originally Posted by r_abhinav

Nothing wrong in ur approach hellion..just a small pit which u overlooked
We will solve step by step

No of Males --> m
No of females --> f

m=2(f-15)

now the second statement is continuation of this statement..so,
(f-15)=2(m-45)

on Solving u get,
m=50
f=40

hope u r clear...
cheers!!!

Now this leaves me confused
Can someone clear it up??

[avinav2712]

Originally Posted by r_abhinav

Nothing wrong in ur approach hellion..just a small pit which u overlooked
We will solve step by step

No of Males --> m
No of females --> f

m=2(f-15)

now the second statement is continuation of this statement..so,
(f-15)=2(m-45)

on Solving u get,
m=50
f=40

hope u r clear...
cheers!!!

I don't think you read the question properly. The second statement is not reflected in the question.... I agree with Hellion's answer although it doesn't seem logical (to have 53.33 males) but this is what we can get from the question

Here's the question and the link for your referral:

http://www.pagalguy.com/forum/quanti...ml#post1121566 (official quant thread for cat08)

"In a club there are certain no. of males and females. If 15 females are absent then no. of males will be twice that of females. If 45 males are absent then female strength will be 5 times that of males. Find no. of males actually present."

[avinav2712]

Originally Posted by hellion

Now this leaves me confused
Can someone clear it up??

Well, Hi2all's approach is wrong..... because of this

f-15=2m (This is the place where u mis understood the question..)

You understood it correctly but unfortunately he didn't.... Here the number of males would be actually half the no. of females and not double as is reqd in the question.... This can be checked from the answer he gets as well

[deep@k]

there is a explanation for infinite trip....

total distance coverd by bird must be at alst = 12 km
s= 8 + 8/3 + 8/9 + 8/27 + 8/81 +...........................

consider that is a infinite GP

so, s= 8(1/(1-1/3)) = 12 km

[deep@k]

Originally Posted by avinav2712

Well, Hi2all's approach is wrong..... because of this



You understood it correctly but unfortunately he didn't.... Here the number of males would be actually half the no. of females and not double as is reqd in the question.... This can be checked from the answer he gets as well

The guy who posted this question .... has to check once because question is wrong....

please check and post correct question......

[avinav2712]

Originally Posted by deep@k

The guy who posted this question .... has to check once because question is wrong....

please check and post correct question......

I think the question as understood by r_abhinav should be the actual question.... Meaning the second statement should take off from where the first one ended.... Only then can we get some proper values... Maybe the original person ate up some words while posting the question.

[implex]

Originally Posted by selebratinglife

No solution?

5 solutions for this !

[jha16june]

Originally Posted by implex

well yeah, if there are two such primes, the question will become ambiguous, the maximum we can do is choose the prime closer to 40!! which is not the best way, but we do not have many other options to chose from !!

Can you explain why will you choose the prime closer to 40. What is the logic?