Question
Boat ‘A’ can cover 160 km in still water in 8 hours.
In still water, if the ratio of the speed of boat ‘A’ to that of ‘B’ is 4:3 and the speed of stream is 3 km/hr then find the time taken by boat ‘B’ to cover the 234 km in downstream.Solution
Speed of boat ‘A’ in still water = 160/8 = 20 km/hr Speed of boat ‘B’ in still water = 20 × (3/4) = 15 km/hr Downstream speed of boat ‘B’ = 15 + 3 = 18 km/hr Time taken by boat ‘B’ to cover 234 km in downstream = 234/18 = 13 hours
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...
The six decile (D6 ) of 5, 3, 2, 6, 8, 4 is:
If Z1, Z2,…Zn are n independent standard normal variates, then Σni=1 Z2i will follow:
Two data set of size 9 and 6 have standard deviation 3 and 4 respectively and arithmetic means 3 and 3 respectively. The standard deviation of combined...
A physical instructor claims that the mean weight of students in school is greater than 82 kg with standard deviation 20. If a sample of size 81 studen...
Which one is not non-probability sample method
For the data set
X: 1 2 3 4 ...
Which of the following is a sources of primary data?
The incomes of the employees in a state is assumed to be normally distributed with mean ₹15,000 and variance ₹900. The median of the distribution o...
For completely randomized design for k treatments and n observations, yif = response from the jth unit receiving ith treatment, �...
Relevant for Exams:
