Let A can do 6 units per day then C can do 4 units per day So days taken by (A+C) together to complete the work = 6 days So total work = (6+4)*6 = 60 units Efficiency of (B+D) = (5+3) = 8 So B & D will do this job in = 60/8 = 7.5 days
A dice was thrown 400 times and 'six' resulted 80 times. The data is used to justify the hypothesis of an unbiased dice at 95% confidence. With referen...
For a group of 100 students, the mean and standard deviation of scores were found to be 30 and 5 respectively. Later on it was discovered that the scor...
If first, second, and third moment about origin are 1, 6, and 15 respectively, then Karl Pearson beta coefficient of skewness β is
The fair dice is rolled 15 times and face value are noted
Face Value:Â Â Â Â Â Â Â Â 1Â Â Â Â Â Â Â Â Â Â Â Â Â 2Â Â Â Â Â Â Â Â Â Â Â Â Â 3...
If the first, fifth and ninth decile of frequency distribution xi ∣ fi are 3,10,16, respectively, then Kelly's coefficient of skewness is:
For ANOVA table
the F - statistics is:
 X and Y are independent normal variables with mean 50 and 80 respectively and standard deviation as 4 and 3 respectively. What is the distribution o...
For the two variables X and Y, the following observations are tabulated
X:Â Â Â Â Â Â Â Â Â Â Â 3Â Â Â Â Â Â Â Â Â Â Â Â Â 4Â Â Â Â Â Â Â Â Â...
The first four moments of a distribution about the origin are -1.5,17,-30 and 108. The third moment about the mean is:
