SOLUTION: A finite arithmetic sequence has 12 terms. The last term is 100 and the common difference is 3.What is the firt term

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Question 1092380: A finite arithmetic sequence has 12 terms. The last term is 100 and the common difference is 3.What is the firt term
Found 2 solutions by Boreal, greenestamps:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
a12=a1+d(n-1); a12 is 100, d=3, n=12
100=a1+3(11)
100=a1+33
a1=67

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!

The 12th term is the first term plus the common difference 11 times; so the first term is the 12th term minus the common difference 11 times.
100+-+11%283%29+=+100-33+=+67