SOLUTION: select the next number in the series: 298 209 129 58 -4 choices are -13, -93, -66, -57

Question 144227: select the next number in the series:
298 209 129 58 -4
choices are -13, -93, -66, -57
Found 2 solutions by stanbon, MathLover1:
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
select the next number in the series:
298 209 129 58 -4
choices are -13, -93, -66, -57
----------------
You take the successive differences and get:
89....80....71...62
-----------------
You take the successive differences again and get:
9.....9....9
-------------------
This tells you the pattern is quadratic
---------------------
Using the form y = ax^2+bx+c you generate three equations by
substituting three points from the following:(1,298) (2,209) (3,129) (4,58) (4,-4)
Doing that will give you three equations in a,b, c.
Solve the system of equations and determine f(6) to get the
next number in the sequence.
-------
I get -57.
==============
Cheers,
Stan H.

Answer by MathLover1(20850) (Show Source): You can put this solution on YOUR website!
select the next number in the series:

let's find a pathern:
��..
��
�.
The difference between and is , the difference between and is ,the difference between and next number will be also less than , so we can write an equation like this:
�.
�.
�.
�.
��.your

RELATED QUESTIONS
What's the next number in the series? 4, 12, 13, 15, 14, 10, 11, 9 ... (answered by Alan3354,math_helper,rothauserc,Edwin McCravy)
A local group claims that the police issue at least 60 speeding tickets a day in their... (answered by ewatrrr)
10.60 interpret it. Heart Rate Before and After Class Break Person Before After (answered by stanbon)
13, 18,14,15,16,13,19 .....what is the next number in the series? what is the rule... (answered by richwmiller)
THE FOLLOWING REPRESENT THE SALARIES(IN THOUSANDS OF DOLLARS) FROM A SMALL SCHOOL... (answered by solver91311)
I need to find the next number in the sequence but not sure how to get there 3, -6,... (answered by Edwin McCravy)
What is the solution to this number series: 4, 7, 11, 14, 23, 27, 35, 39, 51, 64, 70, 85, (answered by ikleyn)
What is the solution to this number series: 4, 7, 11, 14, 23, 27, 35, 39, 51, 64, 70, 85, (answered by ikleyn)
determine the number of terms n in each geometric series. Given that a1=3 r=6 and... (answered by greenestamps)