Quant Basics for Zeros in Quant - CAT 2012

heavensent · January 25, 2012, 2:31pm

I would suggest Book on Numbers.

Numbers Demystified by Nishit K.Sinha.

That's an awesome book if you really wanna have some good knowledge in numbers also sufficient to crack any question on Numbers..obviously with a little presence of mind.

Rgrds

Bhai do u have this book in pdf format ??

heavensent · January 25, 2012, 2:58pm

One problem, sorry if I sound too silly with such sums but, I am nt able to get an answer to:
2 trains travel in opposite directions at 36km.hr and 45km/hr. A man sitting in the slower train passes the faster train in 8 secs. The length of the faster train is?
80
180
120
150
110
Please tell me your approach as well. Only answer is of no use>

Since trains are traveling in opposite direction , their relative speed is = 36 + 45 = 81 km/hr = 81 *5/18 = 45/2 m/s

Hence length of faster train = 45/2 * 8 = 180 m

dvcoolster · January 25, 2012, 2:59pm

Before doing all the preps, a nice read: 6 Minutes of Leak and 60 Questions | Title is under consideration

mehravikas1983 · January 25, 2012, 5:01pm

How does one refer to older material?

bs0409 · January 26, 2012, 12:01am

mehravikas1983 Says
How does one refer to older material?

Which older material you want to refer to??

ajayjr · January 27, 2012, 6:42am

Since trains are traveling in opposite direction , their relative speed is = 36 + 45 = 81 km/hr = 81 *5/18 = 45/2 m/s
Hence length of faster train = 45/2 * 8 = 180 m

Sorry bud can u plz explain the emboldened part!

hydrocker · January 27, 2012, 10:54am

ajayjr Says
Sorry bud can u plz explain the emboldened part!

Since trains are traveling in opposite direction , their relative speed is = 36 + 45 = 81 km/hr
Now convert km/hr in to m/sec. To do that we must multiply with 5/18.
81 *5/18 = 45/2 m/s
Now we know the relative speed. With in 8 seconds the train crosses the man with that relative speed.
distance=speed*time [ Here distance is length of the faster train]
Hence length of faster train = 45/2 * 8 = 180 m

Hope you got it now. No question is silly when it comes to CAT.

ajayjr · January 28, 2012, 6:08am

Hello Friends!!
As we all know, speed is one of the keys to cracking CAT and that will come if we use shortcuts for little calculations like finding squares, cubes, multiplication techniques etc.
I would request all the members of this thread to post whatever litle tricks they are aware of for the benefit of others who are interested in learning them!!

heavensent · January 29, 2012, 5:06am

@ajayjr : Sorry for being late in reply !! But i guess HydRocker have already solved ur problem and he did a pretty good job in explaning.

@all : why this thread is not alive !! Com on guys abhi toh bahut kuch karna hai !!!!

vinayakode · January 30, 2012, 10:32am

Since trains are traveling in opposite direction , their relative speed is = 36 + 45 = 81 km/hr
Now convert km/hr in to m/sec. To do that we must multiply with 5/18.
81 *5/18 = 45/2 m/s
Now we know the relative speed. With in 8 seconds the train crosses the man with that relative speed.
distance=speed*time [ Here distance is length of the faster train]
Hence length of faster train = 45/2 * 8 = 180 m

Hope you got it now. No question is silly when it comes to CAT.

Hi Good Initiative. I am would like to join u guys for Quant preparation. Please let me know which topic are you discussing right now, so that I can start working on those problems and post my queries.

hydrocker · January 30, 2012, 11:17am

vinayakode Says
Hi Good Initiative. I am would like to join u guys for Quant preparation. Please let me know which topic are you discussing right now, so that I can start working on those problems and post my queries.

Percentages, Profit and loss, Ratios and Proportions

vbhvgupta · January 30, 2012, 11:24am

Count me too.......

vbhvgupta · January 31, 2012, 3:37pm

3x-4y+2z=0 & 4x-2y-z=0
find x:z:y.

hydrocker · January 31, 2012, 4:14pm

3x-4y+2z=0 & 4x-2y-z=0
find x:z:y.

solving 3x-4y+2z =0 and 4x-2y-z=0 we get,
11x-8y= 0
11x = 8y
x/y = 8/11

Now again solving 3x-4y+2z =0 and 4x-2y-z=0 we get,
-5x+4z= 0
-5x= -4z
x/z = 4/5

so x:y:z = 8:11:10
Therefore x:z:y = 8:10:11

vbhvgupta · January 31, 2012, 4:23pm

A certain no is added to each of a pair of numbers which are in ratio 4:7. the sum of the resulting numbers is 75 and their ratio(taken in same order as mentioned above) is 8:17.
what is the no added.

hydrocker · January 31, 2012, 4:31pm

A certain no is added to each of a pair of no are in ratio 4:7. the sum of the resulting nos is 75 and their ratio is 8:17..
what is the no added.

Yaar wordings clear nahi hai... Mujhey samaj nahi aa raha hai.. fir se dhek question ko

vbhvgupta · January 31, 2012, 4:54pm

HydRocker Says
Yaar wordings clear nahi hai... Mujhey samaj nahi aa raha hai.. fir se dhek question ko

try it now..

neyatibhanot · January 31, 2012, 5:07pm

-12 is added

A certain no is added to each of a pair of numbers which are in ratio 4:7. the sum of the resulting numbers is 75 and their ratio(taken in same order as mentioned above) is 8:17.
what is the no added.

vbhvgupta · January 31, 2012, 5:08pm

neyati bhanot Says
-12 is added

explain buddy..

bankaspirant · February 1, 2012, 2:22am

hii
frezs
thanx for creating such a nice thread

i am not preparing for the CAT 2012 but i am preparing for the ibps po xam
n think this thread will help me a lot
actually i gave the xam of ibps po n cleared too bt wanna improve my score this time so
soon i will come here with my questions in which i am facing problem:cheers: