Arithmetic Progression: Finding the First Term and Common Difference

[Crystalong876]

The sum of the first 100 terms of an arithmetic progression is 15050; the first, third and eleventh terms of this progression are three consecutive terms of a geometric progression. Find the first term, a and the non-zero common difference, d, of the arithmetic progression.

 

[MarkFL]

Hello and welcome to MHB, Crystalong876! :D

There are several issues of which I need to make you aware:

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So, given these rules and policies at MHB (the complete list can be found http://mathhelpboards.com/rules/), I have moved your first thread here, given it a useful title and then deleted the 3 duplicate threads. Whew! (Sweating)

With that done, can you post what you have tried so far so our helpers know where you are stuck and can best guide you?

 

[Wilmer]

The sum of the first 100 terms of an arithmetic progression is 15050; the first, third and eleventh terms of this progression are three consecutive terms of a geometric progression. Find the first term, a and the non-zero common difference, d, of the arithmetic progression.

Are you able to solve this equation for a:

am = a + 2d

a = ?

If not, you'll need classroom help to solve your problem...