Given information:
- Number of observations: 100
- Mean of the group: 65
- Standard deviation of the group: 7.03
- Number of observations with mean and standard deviation as 70: 60

Explanation:
To understand the given information and find a solution, we need to break down the problem into smaller steps.

Step 1: Understanding Mean and Standard Deviation:
Mean is the average of a set of numbers, calculated by summing all the values and dividing by the total number of observations. Standard deviation measures the dispersion or spread of the data points around the mean.

Step 2: Calculation of Total Sum:
Since we know the mean of the entire group is 65, we can calculate the total sum of all 100 observations.
Mean = Sum of all observations / Total number of observations
65 = Sum of all observations / 100
Sum of all observations = 65 * 100 = 6500

Step 3: Calculation of Total Sum for 60 observations:
We are given that 60 of the observations have a mean of 70. Using the same logic as in step 2, we can calculate the total sum for these 60 observations.
Mean = Sum of 60 observations / 60
70 = Sum of 60 observations / 60
Sum of 60 observations = 70 * 60 = 4200

Step 4: Calculation of Total Sum for the remaining 40 observations:
To find the total sum of the remaining 40 observations, we subtract the sum of the 60 observations with a mean of 70 from the total sum of all observations.
Total sum of remaining 40 observations = Total sum of all observations - Sum of 60 observations
Total sum of remaining 40 observations = 6500 - 4200 = 2300

Step 5: Calculation of New Mean and Standard Deviation:
Now that we have the total sum of the remaining 40 observations, we can calculate the new mean and standard deviation for these observations.
New mean = Total sum of remaining 40 observations / Total number of remaining observations
New mean = 2300 / 40 = 57.5

To calculate the new standard deviation, we need to know the individual values of the 40 observations.