November 10th, 2008, 04:55 AM
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the first term is 200, the last term is 5000. The difference between consecutive terms equal to 150.
so basically the sequence is 200, 350, 500, 650 etc etc all the way to 5000!
now i need to find the number of terms within this sequence Quote:
Originally Posted by HallsofIvy  What, exactly did the problem say? What you've written here makes no sense.
In the sequence 200, 5000, 200 is the first term , 5000 is the last term and there are 2 terms. The sum is 5200 or, using your formula, (2/2)(200+ 5000)= 5200.
In the sequence 200, 2600, 5000, 200 is the first term, 5000 is the last term and there are 3 terms. The sum is 7800 or, using your formula, (3/2)(200+ 5000)= (3/2)(5200)= 3(2600)= 7800.
You cannot find either the number of terms nor the sum of an arithmetic series just from the first and last numbers. You have to know what the series is! | |