Official Quant thread for CAT 2013

MBA CAT 2024
19806
@ani6 said:
To completely fill a half filled tank, tap x is opened and the tank is fully filled in 20 hours. But after 4 hours, the power goes off. Before the power came, exactly half of the water, which was in the tank, had been used. How much time would it take now to fill the tank completely?
Couldn't understand the question! Tap x is opened and tank is fully filled in 20 hours! Tap is opened after the tank is half-filled OR it can fill an empty tank in 20 hours?? Not clear!
19807
@ani6 said:
To completely fill a half filled tank, tap x is opened and the tank is fully filled in 20 hours. But after 4 hours, the power goes off. Before the power came, exactly half of the water, which was in the tank, had been used. How much time would it take now to fill the tank completely?
Couldn't understand the question! Tap x is opened and tank is fully filled in 20 hours! Tap is opened after the tank is half-filled OR it can fill an empty tank in 20 hours?? Not clear!
19808
@ScareCrow28 yah oa is the same..
let sons age one year ago be x then fathers age is 4x
present it will be 4x+7-2(x+7)=9
solving i got x=8 then how to proceed???
19809
@jaswik said:
one year ago a father was 4 times as old as his son. in 6 years time, his age exceeds twice his son's age by 9 years.Ratio of their ages is?
f-1 = 4(s-1)
and f+6 = 2(s+6) + 9

solving u get son=9 and father =33
so 33:9
19810
@jaswik said:
@ScareCrow28 yah oa is the same.. let sons age one year ago be x then fathers age is 4x present it will be 4x+7-2(x+7)=9 solving i got x=8 then how to proceed???
x=8 is 1 yr ago... so son's present age is 9.
since u took x to be one yr ago age.

19811
@jaswik said:
@ScareCrow28 yah oa is the same.. let sons age one year ago be x then fathers age is 4x present it will be 4x+7-2(x+7)=9 solving i got x=8 then how to proceed???
Then just take the ratio (4x+1)/(x+1) You will get the same answer
19812
@ani6 said:
To completely fill a half filled tank, tap x is opened and the tank is fully filled in 20 hours. But after 4 hours, the power goes off. Before the power came, exactly half of the water, which was in the tank, had been used. How much time would it take now to fill the tank completely?
Let total be W
in one hour it fills W/40
in four hours W/10
water in the tank now = W/2 +W/10=3W/5
water left after power cut = 3W/10
water to be filled =7W/10
W/40 in 1 hour
1 L in 40/W hour
7W/10 in 40/W * 7W/10 =28
bhai 13 kaise ho skta h
19813
@ani6 said:
To completely fill a half filled tank, tap x is opened and the tank is fully filled in 20 hours. But after 4 hours, the power goes off. Before the power came, exactly half of the water, which was in the tank, had been used. How much time would it take now to fill the tank completely?
28 hours..??
19814
@ani6 said:
To completely fill a half filled tank, tap x is opened and the tank is fully filled in 20 hours. But after 4 hours, the power goes off. Before the power came, exactly half of the water, which was in the tank, had been used. How much time would it take now to fill the tank completely?
let the capacity of the tank be 40ltr
half tank is already filled, so x fills 20 ltr in 20 hrs ir 1 ltr/hr
after t+4 hrs -> tank filled = 24 ltrs
now half of this is used ie 12 ltr used and 12 left
40-12 = 28 ltr left
hence, x would now take 28 hrs to fill the tank....
19815
@jaswik said:
one year ago a father was 4 times as old as his son. in 6 years time, his age exceeds twice his son's age by 9 years.Ratio of their ages is?
3:11 ???
19816
From a chess board three blocks are chosen at random. What is the probability that the three blocks are from same diagonal?
19817



@ScareCrow28 said:
Let speed of man be x and escalator be n m/s30x - 30n = 20xHence x = 3nSo, time taken will be = 20x/3n+n = 60n/4n = 15 sec..
Dono ek hi direction mai move kar rahe hai to 3n-n kyu nahi
19818
@blowcat13 said:
From a chess board three blocks are chosen at random. What is the probability that the three blocks are from same diagonal?
There are 11 diagonals in chess board which have 3 or more squares. Hence 1/11..??
19819
@blowcat13 said:
From a chess board three blocks are chosen at random. What is the probability that the three blocks are from same diagonal?
112/41664?
19820
@sbharadwaj said:
There are 11 diagonals in chess board which have 3 or more squares. Hence
1/11..??

i think he is only talking abt the center diagnols
19821
@sbharadwaj oa:112/41664
@Subhashdec2 yahh right
19822

P is a set of all factors of 360 and Q is set of all factors of 1200.Find the product of elements of the set P U Q ?????

19823
Three types of animals, cockroach, mice and crow are there in a room. There are totally 50 heads and 150 tails in the room. No of cockroach is twice than the no of mice. What are the no of mice in the room?
a) 5 b) 10 c) 15 d) none of these
19824
@pavimai said:
P is a set of all factors of 360 and Q is set of all factors of 1200.Find the product of elements of the set P U Q ?????
LCM of 360 and 1200?
3600?
19825
@jaswik said:
one year ago a father was 4 times as old as his son. in 6 years time, his age exceeds twice his son's age by 9 years.Ratio of their ages is?
f - 1 = 4(s - 1)
f + 6 = 2(s + 6) + 9
f/s = 11/3 ?