Determine the first term of the arithmetic sequence in which the 16th term is 110 and the common difference is 7

Question

What is the first term of the sequence 

Answer 1

The formula of an arithmetic sequence is as follows: a_n = d(n-1) + a_1

"n" stands for the nth term of the sequence.

 

We know that the 16th term is 110, and the difference "d" is 7.

 

Substituting those into the formula gives us: 110 = 7(16-1) + a_1

 

110 = 7(15) + a_1

110 = 105 + a_1

110 - 105 = a_1

5 = a_1

 

The first term is 5.