Question
The speed of a boat in still water is 6 km/hr more than
that of the current. The time taken by the boat to cover 625 km downstream is 12.5 hours. Find the total time taken by boat to travel 340 km downstream and 45 km upstream.Solution
Therefore, downstream speed of the boat = 625/12.5 = 50 km/hr And, upstream speed of the boat = 6 km/hr Required time taken = (340/50) + (45/6) = 6.8 + 7.5 = 14.3 hours
For the following frequency distribution
Class :                 3-5        5-7         7-9      �...
The first four moments of a distribution about the origin are -1.5,17,-30 and 108. The third moment about the mean is:
The median of the following observations 10, 11, 9, 12, 10,10, 12, 10, 9,11 is:
The mean and median of the distribution are 10 and 11 respectively, then the mode equals to
The sample sizes for two cases were 15 each with means as 104 and 114 respectively and variances as 200 and 510 respectively.
Let the null hyp...
The probability of getting a total of 7 on two dice thrown together is:
With which characteristic movement of a time series would you associate increasing demand of smaller automobiles?
The memory-less property is followed by which of the following continuous distribution:
If first, second, and third moment about origin are 1, 6, and 15 respectively, then Karl Pearson beta coefficient of skewness β is
