80, 90, 40, 30, 20, 10, 70, 60, 50
To find the difference between the two medians, we first calculate the median of the original data and then the median of the data after the replacement.
The original data set is:
80, 90, 40, 30, 20, 10, 70, 60, 50
First, arrange the data in ascending order:
10, 20, 30, 40, 50, 60, 70, 80, 90
There are $n=9$ observations. The median is the middle value, which is the $(\frac{n+1}{2})^{th}$ term.
Median position = $(\frac{9+1}{2}) = 5^{th}$ term.
The 5th term in the sorted list is 50. So, the original median is 50.
Now, replace the number 30 with 100 in the original data set:
80, 90, 40, 100, 20, 10, 70, 60, 50
Arrange this new data set in ascending order:
10, 20, 40, 50, 60, 70, 80, 90, 100
The number of observations is still $n=9$. The median is again the $(\frac{n+1}{2})^{th}$ term.
Median position = $(\frac{9+1}{2}) = 5^{th}$ term.
The 5th term in this sorted list is 60. So, the new median is 60.
The question asks for the difference between the two medians.
Difference = (New Median) - (Original Median)
Difference = $60 - 50$
Difference = $10$
The difference between the two medians is 10.
| Height (cm) | Number of persons |
|---|---|
| 120 | 3 |
| 130 | 4 |
| 140 | 5 |
| 150 | 6 |
| 160 | 2 |
| Value | 3 | 2 | k | 4 | 5 |
| Frequency | k | 2k | 3k | 4k | 5k |
Demand for seats in a university is at its highest in the fall; demand also trends to grow and fall off in 25 year waves. In time service forecasting, the former demand characteristic would be called ______ and the latter would be called _______.
The system of combining two or more overlapping series of index numbers to obtain a single continuous series is called
The rise in the number of patients due to heatstroke is an example of:
According to government data, 24 percent of teenagers in India under the age of 18 years live in households with incomes that are classified at a particular income level. A simple random sample of 400 teenagers in India under the age of 18 years was selected for a study of learning. If the government data is correct, which of the following best approximates the probability that at least 27 per cent of the teenagers in the sample live in households that are classified at a particular income level?
Which index satisfies the factor reversal test?