16)After a get-together every person present shakes the hand of every other person. If there were 105 hands-shakes
in all, how many persons were present in the party?
A 15
B 14
C 13
D 16
7)A class consists of 100 students, 25 of them are girls and 75 boys; 20 of them are rich and remaining poor; 40 of
them are fair complexioned. The probability of selecting a fair complexioned rich girl is:
A. 0.05
B. 0.04
C. 0.02
D. 0.08
8)Which of the following will come in place of the Question Mark (?) in the following sequence?
6C7, 5F10, 11J14, 15O19, ?
A 25U20
B 20U25
C 20U24
D 19U25
9). A box contains 5 brown and 4 white socks. A man takes out two socks. The probability that they are of the same
color is:
A 5/18
B 1/6
C 5/108
C 4/9
10)If the price of gold increases by 30%, find by how much the quantity of ornaments must be reduced so that the expenditure may remain the same as before?
A. 30%
B. 23 1/3 %
C. 20%
D. 19%
11)The amount of water (in ml) that should be added to reduce 9 ml lotion, containing 50% alcohol, to a lotion
containing 30% alcohol, is:
A. 5 ml
B. 4 ml
C. 3 ml
D. 6 ml
12)The average age of 8 persons in a committee is increased by 2 years when two men aged 35 years and 45 years
are substituted by two women. The average age of these two women is:
A. 52 years
B. 56 years
C. 48 years
D. 44 years
13)A mixture of 40 liters of milk and water contains 10% water. How much water should be added to this so that water may be 20% in the new mixture?
A. 6.5 liters
B. 5 liters
C. 4 liters
D. 7.5 liters
Plz solve these sums.
21
omkar
·2010-06-17 03:49:30
6)
ans is 15
no. of handshake= 15C2/2 =105
39"Plz show that u hv mde sum effort urself and we wil help u. if u r 2 lazy 2 attempt d sums, we r 2 lazy 2 help. Use http://answers.yahoo.com 4 HHW"
Otherwise sibal is always there.
494. (d)
area of b is 4 times area of a
rad of b is 2 times rad of a
vol of b is 8 times the vol of a
a is 7/8 times that is 87.5% less than vol of b.
mera kya if u are making us solve ur holiday homework....all that matters to me is that i am having a nice practice :P
49
Subhomoy Bakshi
·2010-06-17 15:58:47
1) no of ways they can sit= 7!
let us seat the girls and place boys in the left 4 places
thus, no of ways = 3! X 4!
probability= 3! X 4!7!=135
49
Subhomoy Bakshi
·2010-06-17 16:03:31
2)for question number 2 please clarify wether the distance 2 km is the dist b/w head of 2 trains or tail of the one in front and head of the tain behind.
if 2 km is the dist b/w tail of the one in front and head of the tain behind,
let the time taken to overtake be t.
distance travelled by first train= 20t
distance travelled by second train= 30t
by the problem,
30t=20t+200+2000+300
giving, t= 250 seconds= 416mins.
49
Subhomoy Bakshi
·2010-06-17 16:10:16
3) the length of each side is 14 cm.
so area available to each tethered horse=quadrant of radius 7cm = 14Ï€X(7)2=1544 cm2.
total area grazed in 11 days= 4X1544 cm2= 154 cm2.
total area present in square= 194 cm2.
now,
case-1::the horses are still tethered to the corners, time taken to graze the rest grass is ∞ days. [3][3]
case-2:: the tetherings of the horses are opened.
time taken to graze left 50 cm2= 5014=347days ~ 4 days.
49
Subhomoy Bakshi
·2010-06-17 16:13:56
5) actually the given is (x+1)(x-1):(x+2)(x-1)=9:10
so, x=0,8
we can ignore value 0
thus answer is 8
49
Subhomoy Bakshi
·2010-06-17 16:15:42
n persons in party, shakes hand with n-1 people...
but a shaking hand with b is equivalent to b shaking hand with a.
so no of handshakes= n(n-1)/2 = 105
n(n-1)= 210
n=15.
49
Subhomoy Bakshi
·2010-06-17 16:15:55
6)n persons in party, shakes hand with n-1 people...
but a shaking hand with b is equivalent to b shaking hand with a.
so no of handshakes= n(n-1)/2 = 105
n(n-1)= 210
n=15.
49
Subhomoy Bakshi
·2010-06-17 16:24:42
6)i use venn diagram for this...
P= (no of rich fair complextioned girls)/100
hehehehe...for me the probability is 1 :P:P