First one
Avg rate of change from 0 to 2
We have the points at x = 0 and x = 2 of (0, 2) and ( 2, 1)
The average rate of change is just the slope between these points =
[ 1 - 2 ] / [ 2 - 0 ] = -1 /2
Second one
Avg rate of change on [ 3, 5 ]
We have the points ( 3,59) and (5,53)
The avg rate of change is just the slope between the points =
[ 53 - 59 ] / [ 5 - 3 ] = -6 / 2 = -3
Last one
We have the points ( 1, 484) and ( 4,244)
Avg rate of change = [ 244 - 484 ] / [ 4 - 1 ] = -240 / 3 = -80