the sum of the 1st and 17th teram is 40.thr sum of 1st and 18th teram is 43.whatbisits 7th and 11th teram
Answers
Answered by
0
Step-by-step explanation:
the nth term of an arithmetic sequence is an = a1 + (n-1)d.
The 16th term is a1 + 16d and the sum of the first and 17th term is 2a1 + 16d = 40
Likewise or the 18th term, the sum required is 2a1 + 17d = 43
The difference of these 2 sums is clearly d = 3
Similar questions