If the mean of $a$, $b$, and $c$ is $M$; $ab + bc + ca = 0$; and the mean of $a^2$, $b^2$ and $c^2$ is $KM^2$, then $K$ is equal to

In a cricket team of 11 players, the average age is 28 years. Out of these, the average ages of three groups of three players each are 25 years, 28 years, and 30 years respectively. If in these groups, the captain and the youngest player are not included and the captain is eleven years older than the youngest player, then the age of the captain is

Let x be median of the data $13, 8, 15, 14, 17, 9, 14, 16, 13, 17, 14, 15, 16, 15, 14.$ If $8$ is replaced by $18$, then the median of data is $y$, then the sum of $x$ and $y$ is equal to:

Match List I with List II. Choose the correct answer from the options given below:

The mean of 25 observations is 36. If the mean of the first 13 observations is 32 and that of the last 13 observations is 39, then the 13th observation is:

The average of five consecutive numbers is a. If the next two numbers are also included, how will the average vary?

A car owner buys petrol at the rate ₹ 17, ₹ 19 and ₹ 20 per litre, respectively for three consecutive years. Compute the average cost per litre, if he spends ₹ 6,460 per year for the three consecutive years.