Answer:
- 9
Step-by-step explanation:
We require
- 15 , m₁, m₂, m₃, 9
The average of the end values gives m₂ , that is
m₂ = [tex]\frac{-15+9}{2}[/tex] = [tex]\frac{-6}{2}[/tex] = - 3
Similarly, the average of - 15 and m₂ gives m₁
m₁ = [tex]\frac{-15-3}{2}[/tex] = [tex]\frac{-18}{2}[/tex] = - 9
The first arithmetic mean m₁ = - 9