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#1 Help Me ! » Number Sequence, Is there a relevant formula? Please show me the steps » 2015-12-13 15:12:37

place value
Replies: 3

hello everyone,

I am preparing for an exam. In brief, my exam practice book shows the following number sequence:
20, 30, 50. And asks what is the next number in the sequence?
The answer that the book gives is 80.

Years ago, when I took a math class, i remember there being a formula for arithmetic and geometric number sequence problems. Now, as I look at these formulas I can't seem to understand which of these formulas applies here. I understand that there is a steady increase on top of the cumulative total.

Term 1     Term 2              Term 3                Term 4                    so on and so forth ...     
                term 1 + 10       term 2 + 20         term 3 + 30
= 20           = 30                  = 50                    = 80

   
My question, is there a formula that would tell me the 300th term in this sequence?

your help is much appreciated,
thanks

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