yes you are right please tell me the steps.
@kingsleyx said:A simple one :A couple has two children. The probability that the first child is a girl, is 50%. The probability that the second child is a girl, is also 50%. They tell you that they have a daughter. What is the probability that their other child is also a girl ?
1/3
Because it is mentioned that.. one of the children is Daughter.. sample space of the event becomes { DD, DS, SD}
Probablity of both the children to be daughters is = P(DD) = 1/3
@kingsleyx said:A simple one :A couple has two children. The probability that the first child is a girl, is 50%. The probability that the second child is a girl, is also 50%. They tell you that they have a daughter. What is the probability that their other child is also a girl ?
first is daughter
DD->1/2*1/2
DS->1/2*1/2
1/2
Is it right?
@gnehagarg said:first is daughterDD->1/2*1/2DS->1/2*1/21/2Is it right?
I did not get this..
But, It is not said that first is daughter.. They tell you that they just have a daughter.
@kingsleyx said:A simple one :A couple has two children. The probability that the first child is a girl, is 50%. The probability that the second child is a girl, is also 50%. They tell you that they have a daughter. What is the probability that their other child is also a girl ?
1/3 is the ans?
@gnehagarg said:first is daughterDD->1/2*1/2DS->1/2*1/21/2Is it right?
See there are 4 possiblities. DD,SD,DS,SS. Now we know one is a D. Hence we know that it cannot be SS. Now so the probability of DD wud be 1/3 !!
@gupanki2 said:Kunal has only 25 paise and 50 paise coins with him. The total amount in 50 paise denomination is Rs 4 more than the total amount in 25 paise denomination. The no. of 25 paise coins is 20 more than the number of 50 paise coins. What s the total amount with kunal?
.5x=4+.25y
y=20+x
.5x=4+.25(20+x)
.25x=9
x=36
y=56
18
If n is a natural number such that 10^12
a 13
b 12
c 11
d 10
@nick_baba said:You live 3km from the office, and you take an auto rickshaw to work every morning. Given how busy Mumbai Road is in Hyderabad, you have observed that 4 out of every 5 mornings, your auto rickshaw driver gets quite close to making an accident. If you move closer to the office, and now only live 1km away, how often do you expect to have a clear run with no close calls to the office?@anytomdickandhary @sujamait @Angadbir @Brooklyn @naga25french @krum @scrabbler @deedeedudu @techsurge@Estallar12 ..can u all please elaborate the concept behind it...i don't have an OA to it..
I will go with 1/(cuberoot(5)).
My logic is - let us assume 3 stretches of 1 km each. Now let the chances of his clearing 1 such stretch without accident be 'x'. Then the chances of his clearing all three will be x * x * x = x^3. But according to the problem, this is 1/5 (since prob of accident is 4/5) Hence x = cuberoot(1/5) = 1/(cuberoot(5)) which is a little below 0.6 (0.58 says the calculator)
Edit: And I see that @chillfactor beat me to it long ago. In my defense, I was in a long distance train :)
regards
scrabbler
My logic is - let us assume 3 stretches of 1 km each. Now let the chances of his clearing 1 such stretch without accident be 'x'. Then the chances of his clearing all three will be x * x * x = x^3. But according to the problem, this is 1/5 (since prob of accident is 4/5) Hence x = cuberoot(1/5) = 1/(cuberoot(5)) which is a little below 0.6 (0.58 says the calculator)
Edit: And I see that @chillfactor beat me to it long ago. In my defense, I was in a long distance train :)
regards
scrabbler
@kingsleyx said:4/15 ??
@catter2011 said:11 out of 15 ?
This cannot be linear....else if we make the distance more than 15/4 the probability of an accident becomes greater than 1 (check it)!
regards
scrabbler
N is the sum of the squares of three consecutive odd numbers such that all the digits of N are the same. If N is a four-digit number, then the value of N is
A. 3333
B. 5555
C. 7777
D. 9999
@htomar said:N is the sum of the squares of three consecutive odd numbers such that all the digits of N are the same. If N is a four-digit number, then the value of N isA. 3333B. 5555C. 7777D. 9999
(n - 2)^2 + n^2 + (n + 2)^2 = answer
3n^2 + 8 = 5555
n^2 = 1849
=> n = 43
n^2 = 1849
=> n = 43