1
GATE ECE 2014 Set 4
+1
-0.3
If calls arrive at a telephone exchange such that the time of arrival of any call is independent of the time of arrival of earlier of future calls, the probability distribution function of the total number of calls in a fixed time interval will be
A
Poisson
B
Gaussian
C
Exponential
D
Gamma
2
GATE ECE 2014 Set 3
+1
-0.3
An unbiased coin is tossed an infinite number of times. The probability that the fourth head appears at the tenth toss is
A
$$0.067$$
B
$$0.073$$
C
$$0.082$$
D
$$0.091$$
3
GATE ECE 2014 Set 1
+1
-0.3
Let $$X$$ be a real - valued random variable with $$E\left[ X \right]$$ and $$E\left[ {{X^2}} \right]$$ denoting the mean values of $$X$$ and $${{X^2}}$$, respectively. The relation which always holds true is
A
$${\left( {E\left[ X \right]} \right)^2} > E\left[ {X{}^2} \right]$$
B
$$E\left[ {X{}^2} \right] \ge {\left( {E\left[ X \right]} \right)^2}$$
C
$$E\left[ {X{}^2} \right] = {\left( {E\left[ X \right]} \right)^2}$$
D
$$E\left[ {X{}^2} \right] > {\left( {E\left[ X \right]} \right)^2}$$
4
GATE ECE 2014 Set 1
Numerical
+1
-0
In a housing society, half of the families have a single child per family, while the remaining half have two children per family. The probability that a child picked at random, has a sibling is _______.