The mean of the five observations x, x + 2, x + 4, x + 6, x + 8 is 11. Then, the mean of the first three observations is
12
2
20
9
A bag has 5 red marbles, 4 green marbles and 3 blue marbles. All marbles are identical in all respects other than colour. A marble is taken out from the bag without looking into it. What is the probability that it is a non-green marble?
Histogram is used to represent
non-continuous grouped frequency distribution
ungrouped frequency distribution
continuous grouped frequency distribution
All of the above
A bag contains 4 black balls, 6 blue balls, 3 white balls and 5 red balls. One ball is drawn from the bag. Probability that the ball drawn is black or white
Mode of the given data 25, 23, 22, 21, 24, 23, 25, 23, 22, 21, 23, 24, 23, 22, 23 is
23
22
21
24