Given Information:
- Mean of 100 observations = 50
- Median of 100 observations = 52
- The greatest observation 110 was misread as 100

To find:
- Correct mean and median

Solution:

Step 1: Find the sum of all observations
- The mean is the sum of all observations divided by the total number of observations.
- Mean = Sum of all observations / Total number of observations

Given that the mean is 50, we can write the equation as:
50 = Sum of all observations / 100

Cross-multiplying, we get:
Sum of all observations = 50 * 100 = 5000

Step 2: Find the sum of all observations by replacing the misread observation with the correct value.
- The greatest observation was misread as 100 instead of the correct value, which is 110.
- So, we need to subtract 100 and add 110 to the sum of all observations calculated in Step 1.

Correct sum of all observations = Sum of all observations - Misread value + Correct value
= 5000 - 100 + 110
= 5010

Step 3: Find the correct mean
- The correct mean can be calculated by dividing the correct sum of all observations by the total number of observations.

Correct mean = Correct sum of all observations / Total number of observations
= 5010 / 100
= 50.1

Therefore, the correct mean is 50.1.

Step 4: Find the correct median
- The median is the middle value of a set of observations when they are arranged in ascending order.
- Since the misread value was the greatest observation, we need to replace it with the correct value, 110, and then find the median.

Observations arranged in ascending order: ... 50, 52, ..., 110 ...

Since there are 100 observations, the median will be the 50th observation. As the observations are arranged in ascending order, the 50th observation will be 55.

Therefore, the correct median is 55.

Final Answer:
- Correct mean = 50.1
- Correct median = 55