Find the indicated terms of the arthmetic sequence. Please explain how.
T3=81, T12=87; determine T23
Because we are given only two members of the sequence, all we can
do is calculate the size of each step between the two.
The difference in value from T3 to T12 is 6.
From T3 to T12 is 9 steps.
The size of each step is 6/9 = 2/3.
From T12 to T23 is 11 steps.
The change in value over those 11 steps is...
11 * 2/3 = 7 1/3
The final value is the value at T12 plus the increase...
87 + 7 1/3 = 94 1/3
T23 = 94 1/3