Answer: the missing term of the sequence is - 103
Explanation:
In an arithmetic sequence, the consecutive terms differ by a common difference. The formula for determining the nth term of an arithmetic sequence is expressed as
Tn = a + d(n - 1)
Where
a represents the first term of the sequence.
d represents the common difference.
n represents the number of terms in the sequence.
From the information given,
a = 221
d = 217 - 221 = 213 - 217 = - 4
n = 82
We want to determine the value of the 82nd term, T82. Therefore,
T82 = 221 - 4(82 - 1)
T82 = 221 - 4 Ă— 81
T82 = 221 - 324
T82 = - 103