Wednesday

April 16, 2014

April 16, 2014

Posted by **Anonymous** on Wednesday, September 26, 2007 at 1:16am.

A. 165

B. 171

C. 249

D. 168

Please explain. thanks

- math-algebra -
**PsyDAG**, Wednesday, September 26, 2007 at 12:21pmSubtract the difference from the last term

**13**times, since the last term is the 14th number. Can you think of a faster way to do this?

I hope this helps. Thanks for asking.

- math-algebra -
**tchrwill**, Wednesday, September 26, 2007 at 2:16pmThe last term of an arithmetic sequence is 207, the common difference is 3, and the number of terms is 14. What is the first term of the sequence?:

A. 165

B. 171

C. 249

D. 168

Please explain. thanks

The last, or nth, term of an arithmetic progression is defined by L = a + (n - 1)d where L = the last term, a = the first term, n = the number of terms and d = the common difference.

Therefore, 207 = a + (14 - 1)3

...............= a + 39

Therefore, a = 207 - 3396 = 168.

**Related Questions**

Maths - 1..The first 2 terms of a geometric progression are the same as the ...

Math - A sequence is formed by adding together the corresponding terms of a ...

arithmetic - The first term of an arithmetic sequence is -3 and the fifteenth ...

Arithmetic Sequence - Given the third term of an arithmetic sequence less than ...

Math for Educators - The first difference of a sequence is 8, 12, 16, 20,... The...

algebra - the third term of an arithmetic sequence is 14 and the ninth term is...

Mathematics : Arithmetic Sequence - The 5th term and the 8th term of an ...

math - first term of the arithmetic sequence is 13. two other terms of the ...

Precalculus - The 8th term in an arithmetic sequence is 5, and the sum of the ...

Algebra - Determine whether each sequence is arithmetic or geometric. Find the ...