SOLUTION: Consider the series: 68, 81, x, 113, 132, find the value of x?

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Question 359548: Consider the series: 68, 81, x, 113, 132, find the value of x?
Found 2 solutions by vleith, Fombitz:
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
Look at the first difference between each pair of terms
81-68 = 13
x-81 = ?
113-x = ??
132-113 = 19
Do you see a pattern in the second list of numbers?
13, 15, 17, 19 ?? Each one is 2 greater than the one before.
You take it from there

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Look at the first differences,
d1=81-68=13
d2=x-81
d3=113-x
d4=132-11=19
Looks like the second differences vary from each other by 2.
So the missing values should be 15 and 17.
x-81=15
x=96
.
.
113-x=17
x-96
.
.
highlight%28x=96%29