Answer:
9, 11 , 13
Step-by-step explanation:
Find the average of 7 and 15, that is
[tex]\frac{7+15}{2}[/tex] = [tex]\frac{22}{2}[/tex] = 11
We now have 7, 11, 15
Now find the average of 7 and 11, 11 and 15
[tex]\frac{7+11}{2}[/tex] = [tex]\frac{18}{2}[/tex] = 9
[tex]\frac{11+15}{2}[/tex] = [tex]\frac{26}{2}[/tex] = 13
Thus the 3 arithmetic means between 7 and 15 are
9, 11, 13