The part D is the correct one...
Given:





To find:
The variance. of combined set.
Solution:
Formula for variance is
...(i)
Using (i), we get




Similarly,




Now, after combining both sets, we get




Therefore, the variance of combined set is 15.4.
I think that it is geometry.
Answer:
x - 3 ≥ 1
Step-by-step explanation:
Solving each of the inequalities
x + 3 ≥ 1 ( subtract 3 from both sides )
x ≥ - 2
3x ≥ 1 ( divide each inequality by 3 )
x ≥ 
x - 3 ≥ 1 ( add 3 to both sides )
x ≥ 4 ← required solution
The average rate of change between 1991 and 1996 is 40 million
<h3>How to determine the average rate of change between 1991 and 1996?</h3>
The given parameters are:
Population in 1991 = 1.5 billion
Population in 1996 = 1.7 billion
The average rate of change between 1991 and 1996 is calculated as:
Rate = (1.7 billion -1.5 billion)/(1996 - 1991)
Evaluate
Rate = 40 million
Hence, the average rate of change between 1991 and 1996 is 40 million
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