Write the arithmetic sequence that has four arithmetic means between -20 and 20.
Solution:-
The rule of arithmetic sequence
{a, a+d, a+2d, a+3d, … }
a = -20
6th term = 20
a+5d = 20
-20+5*d = 20
d = 8
four arithmetic means between -20 and 20
-12,-4,4,12