If the arithmetic mean of 7, 5, 13, x and 9 is 10, then the value of x is

For which set of number do the mean, median and mode all have the same value?

For the set of numbers 2, 2, 4, 5 and 12, which of the following statements is true?

If the mean of five observations x, x+2, x+4, x+6, x+8, is 11, then the mean of first three observations is

Mode is