Official Quant thread for CAT 2013

MBA CAT 2024
27168
@piyushrohella12 said:
shdnt it b CBD 2000 + 2000(0.8) + 2000(0.8)^2 +.....i can say 1 month mei hi clear ho gya debt may b 2 monthdo u have a solution given in the buk
_________/\______

namashkar malik
good to c u back

bhai hona to CBD hee chea.....
but book wale dekhna chahte h ki hume sum to infinity aata h na ya nahi...:P

to 10000 ho jaega shayad
27169
@maroof10 750 gm!!
27170
@Asfakul said:
If we generalize it - is it something like C(n-1,r-1) n= total number of box and r= number of box taken at a time ?
seems correct to me atleast in this case
bt my personal experience
never generalise in P n C the topic is too huge :)
27171
@Subhashdec2 said:
_________/\______namashkar malikgood to c u backbhai hona to CBD hee chea.....but book wale dekhna chahte h ki hume sum to infinity aata h na ya nahi...to 10000 ho jaega shayad
had u not asked me to give those buks i wudnt have opened the account had messages of 2 months back :D
buk valo ka kya hai kuch bhi likhte hai CBD hi hoga
2 men and 3 women can do a work exactly in 20 days . If 3 men and 1 women can do the work in less than 20 days,then 1 men and 5 women can do the same work in
20
>20
CBD
whts ur take myn is CBD confirm
27172
@piyushrohella12 said:
shdnt it b CBD 2000 + 2000(0.8) + 2000(0.8)^2 +.....i can say 1 month mei hi clear ho gya debt may b 2 monthdo u have a solution given in the buk
ans is 10,000 use GP formula sum to infinity a/1-r
27173
@rnishant231 said:
every packets will come 10 times in the combination with other packets.and there will be 15 total combination.so , 10(p1+p2+....+p6)/15 = 0.5OA = 750 gm
Any rule on how many times a packet would be repeated ?
27174
@Asfakul said:
Any rule on how many times a packet would be repeated ?
we can find out like this :
given that combinations are done by taking 4 packets at a time.
assume out of 6 packets (A,B,C,D,E,F) we select A , then in how many we can select other 3 packets out of remaining 5 = 5C3 = 10...hence packet A gets repeated 10 times and so does others

I think No need to generalize this as it can be orally calculated.
27175
@piyushrohella12 said:
had u not asked me to give those buks i wudnt have opened the account had messages of 2 months back buk valo ka kya hai kuch bhi likhte hai CBD hi hoga2 men and 3 women can do a work exactly in 20 days . If 3 men and 1 women can do the work in less than 20 days,then 1 men and 5 women can do the same work in20>20CBD whts ur take myn is CBD confirm
can you pls post your approach ?
27176

Q39 & 40

27177
@vbhvgupta said:
Q39 & 40
39A?
40D?
27178
@ChirpiBird said:
39A?40D?
approach
27179
39. 15?
27180
@vbhvgupta Q39 -A
Q40-D
27181
@rnishant231 said:
we can find out like this :given that combinations are done by taking 4 packets at a time.assume out of 6 packets (A,B,C,D,E,F) we select A , then in how many we can select other 3 packets out of remaining 5 = 5C3 = 10...hence packet A gets repeated 10 times and so does othersI think No need to generalize this as it can be orally calculated.
thanks .. nice
27182
@vbhvgupta said:
approach
ram .. x ques attempted,30%wrong, so total marks will be 1.4x-0.3x...
and 1.1x = Pass + 40......eq1
shyam y ques attempted,40%wrong,so total marks 1.2y-0.4y
and 0.8y= pass +25........eq2

subtract both eq 1and 2.
1.1x-0.8y=15

also, x+y = 100
solve , u'll get x= 50

put in eq1 to get pass marks.

for q40. total marks = 80*2.
ram scored 1.1*50=55
55*100/160 = 34.375


27183
@vbhvgupta x+y = 100 difference between the marks 40-25 = 15
0.7*2x - 0.3x - (0.6*2y - 0.4y) = 15
Solve this

27184

@vbhvgupta let no of attempt by Ram be x and by Shyam be y.
therefore ,
marks of Ram=1.4x-0.3x=1.1x.
marks of Shyam= 1.2y-0.4y=0.8y
Let passing marks be p,
now, 1.1x=p+40
0.8y=p+25
x+y=100
solving them we get p=15 marks.

therefore marks by Ram=55.
total possible marks=160
therefore Ram's %= 34.**!!


27185
@piyushrohella12 said:
had u not asked me to give those buks i wudnt have opened the account had messages of 2 months back buk valo ka kya hai kuch bhi likhte hai CBD hi hoga2 men and 3 women can do a work exactly in 20 days . If 3 men and 1 women can do the work in less than 20 days,then 1 men and 5 women can do the same work in20>20CBD whts ur take myn is CBD confirm
1 man takes A days to complete W
1 woman takes B days to complete W

2/A +3/B=1/20
3/A + 1/B >1/20
3/A +1/B =1/20+x

7/A=1/10+3x
1/A =1/70 +3x/7
7/B=3/20-2/20-2x
7/B=1/20-x
1/B=1/140-x/7

1/A+5/B =1/70 +5/140 +3x/7 -5x/7
1/A +5/B =7/140 -2x/7
1/A+5/B=1/20-2x/7
1/A+5/B

hence they will do it in more than 20 days


27186
@vbhvgupta said:
Q39 & 40
diff in their marks = 15
so x+y =100 and 1.1x - 0.8y = 15 so x =50

1) A
2) D
27187

A person can dig a trench 40 m in depth in 4 days working 8 hrs a day.However,after every day he finds 1/5th of the depth got filled up with mud again. In how many days can he dig a trench 30m in depth?