Official Quant thread for CAT 2013

MBA CAT 2024
6981
The owner of Cheap and Best, a kirana shop, bought some apples at 4 per rupee and an equal number at 5 per rupee. He then sold the entire quantity at 9 for 2 rupees. What is his percentage profit or loss?
a) 1.23% loss
b) 6.66% loss
c) 3.33% profit
d) No profit no loss
ďťże) None of these
6982
@grkkrg said:
The owner of Cheap and Best, a kirana shop, bought some apples at 4 per rupee and an equal number at 5 per rupee. He then sold the entire quantity at 9 for 2 rupees. What is his percentage profit or loss?a) 1.23% loss
a ??
6983

Ashish is studying late into the night and id hungry . He opens his mother's snack cupboard without switching on the lights . Knowing that his mother has kept 10 packets of chips and biscuits in the cupboards . He pulls out 3 packets from the cupboards and all of them turn out to be chips . what is the probability that the snack cupboard contains 1 packets of biscuits and 9 packets of chips ?

6984
@ajeetaryans said:
Ashish is studying late into the night and id hungry . He opens his mother's snack cupboard without switching on the lights . Knowing that his mother has kept 10 packets of chips and biscuits in the cupboards . He pulls out 3 packets from the cupboards and all of them turn out to be chips . what is the probability that the snack cupboard contains 1 packets of biscuits and 9 packets of chips ?
7/128?

3 packets are already taken out
Favourable cases:
BCCCCCC
7

Sample space:
2^7
6985
@grkkrg said:
7/128?

3 packets are already taken out
Favourable cases:
BCCCCCC
7

Sample space:
2^7
6/55
12/73
14/55
7/50
these are option
pls chill sir,jain4444 solve my problem
6986
@gnehagarg 😞 answer is 32... as also solved by grkkrg
below my question...
Let x be the number of 50p coins and y be the number of 25p coins.

50x = 25y + 400
y = 20 + x

50x = 500 + 25x + 400
25x = 900
x = 36
y = 56

Total amount = 50x + 25y = 1800 + 1400 = 3200 paise = Rs.32
6987
@ajeetaryans said:
6/55 12/73 14/557/50these are option pls chill sir,jain4444 solve my problem
i am getting 1/128.. none of the options

Nothing is mentioned.. about order, similarity or distinctness about the chips and biscuits
6988

the answer sheets of 5 engineering students can be checked by any one of 9 professors . what is the probability that all the 5 answer sheets are checked by exactly 2 professors ?

6989
@grkkrg said:
The owner of Cheap and Best, a kirana shop, bought some apples at 4 per rupee and an equal number at 5 per rupee. He then sold the entire quantity at 9 for 2 rupees. What is his percentage profit or loss?a) 1.23% lossb) 6.66% lossc) 3.33% profitd) No profit no lossďťże) None of these
1.23% loss??
6990
@ajeetaryans said:
the answer sheets of 5 engineering students can be checked by any one of 9 professors . what is the probability that all the 5 answer sheets are checked by exactly 2 professors ?
options???

6991
@ajeetaryans said:
the answer sheets of 5 engineering students can be checked by any one of 9 professors . what is the probability that all the 5 answer sheets are checked by exactly 2 professors ?
Is it 432?
6992
@ajeetaryans said:
the answer sheets of 5 engineering students can be checked by any one of 9 professors . what is the probability that all the 5 answer sheets are checked by exactly 2 professors ?


(9c2*30)/(9c1+9c2*30+9c3*150+9c4*240+9c5*120)

=1080/(9+1080+12600+30240+15120)
=1080/59049
=40/2187
6993
@Shray14 said:
options???

20/2187
40/2187
40/729
6994
@htomar said:
Is it 432?
Not 432... may be 288.
6995
@htomar said:
Not 432... may be 288.
@ajeetaryans said:
20/218740/218740/729
That was GROSS.. I was calculating no. of arrangements
6996
@krum said:
(9c2*30)/(9c1+9c2*30+9c3*150+9c4*240+9c5*120)
bro approach??
6997
@Shray14 said:
bro approach??
either 1 or 2 or 3 or 4 or 5 professors can correct the papers
1 prof - 9c1
2 prof - 9c2*(no of ways of distributing 5 diff. objects in 2 diff box.)
{4 1 - 5c1*2=10
3 2 - 5c2*2=20
total = 30}
3 prof - 9c3*(no of ways of distributing 5 diff. objects in 3 diff box.)
4 prof - 9c4*(no of ways of distributing 5 diff. objects in 4 diff box.)
5 prof - 9c5*(no of ways of distributing 5 diff. objects in 5 diff box.)
6998
@krum said:
(9c2*30)/(9c1+9c2*30+9c3*150+9c4*240+9c5*120)=1080/(9+1080+12600+30240+15120)=1080/59049=40/2187
got the same.
6999
@ajeetaryans said:
Ashish is studying late into the night and id hungry . He opens his mother's snack cupboard without switching on the lights . Knowing that his mother has kept 10 packets of chips and biscuits in the cupboards . He pulls out 3 packets from the cupboards and all of them turn out to be chips . what is the probability that the snack cupboard contains 1 packets of biscuits and 9 packets of chips ?
b + c = 10 => Total = 11 possibilities

When 10 chips, 0 biscuits => P(3 chips) = 120/120
When 9 chips, 1 biscuit => P = 9C3/10C3 = 84/120
When 8 chips, 2 biscuit => P = 8C3/10C3 = 56/120
and so on...

P = 84/(120 + 84 + 56 + 35 + 20 + 10 + 4 + 1) = 14/55 ?
7000
@ajeetaryans said:
the answer sheets of 5 engineering students can be checked by any one of 9 professors . what is the probability that all the 5 answer sheets are checked by exactly 2 professors ?
40/2187?

Favourable cases:
Select 2 professors: 9C2
Distribute 5 papers:
2^5 - 2! = 30
Total = 1080

Sample space:
Select 1 prof: 9C1 = 9
Select 2 prof: 9C2 * (2^5 - 2!) = 1080
Select 3 prof: 9C3 * (3C1 * 5C1 * 4C2 + 3C1 * 5C2 * 2!) = 84 * (90 + 60) = 12600
Select 4 prof: 9C4 * 4C1 * 5C2 * 3! = 126 * 240 = 30240
Select 5 prof: 9C5 * 5! = 126 * 120 = 15120
Total = 59049

Probability = 1080/59049
= 120/6561
= 40/2187