What are the next two numbers in the pattern: 7, 14, 28, 56?
1 Answer
Explanation:
This is a geometric sequence. Its exponential growth model is:
So lets plug in some values:
For the first term:
Because anything to the power of 0 is 1, this ends up being 7.
This equation works for any of the terms. Plug in 5 and 6 for the term numbers
If you prefer a simpler approach which is good for nice round numbers like these, just notice that it is doubling every time, starting with 7. Double a term and you get the next.
Here is how to find the model for a sequence like this:
Divide one term by the previous one to find the common ratio.
In this case, it's 2.
Assume the first term is where
Then plug it into the formula: