SOLUTION: find the missing term between -5 and -2

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Question 1138280: find the missing term between -5 and -2
Found 4 solutions by greenestamps, MathLover1, ikleyn, MathTherapy:
Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


Without any more information than that, the missing number could be anything....

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

find the missing term between -5 and -2
if given terms of arithmetic sequence
-5 ,a%5B2%5D,-2
first we need to find common difference d:
a%5B1%5D=-5
a%5B3%5D=-2
a%5Bn%5D=a%5B1%5D%2B%28n-1%29d
a%5Bn%5D=-5%2B%28n-1%29d
2nd term is:
a%5B2%5D=-5%2B%282-1%29d
a%5B2%5D=-5%2Bd........eq.1
3rd term is:
a%5B3%5D=-5%2B%283-1%29d
-2=-5%2B2d
-2%2B5=2d
2d=3
d=3%2F2=>common difference

and, nth term formula is:
a%5Bn%5D=-5%2B%28n-1%29%283%2F2%29
then, 2nd (eq.1) term is:
a%5B2%5D=-5%2B3%2F2=+-7%2F2=-3.5

check all terms:
a%5Bn%5D=-5%2B%28n-1%29%283%2F2%29
n=1
a%5B1%5D=-5%2B%281-1%29%283%2F2%29=-5%2B0%283%2F2%29=-5
n=2
a%5B2%5D=-5%2B%282-1%29%283%2F2%29=-5%2B%283%2F2%29=-7%2F2=-3.5
n=3
a%5B3%5D=-5%2B%283-1%29d=-5%2B2%2A%283%2F2%29=-2




Answer by ikleyn(52818) About Me  (Show Source):
You can put this solution on YOUR website!
.

As a Math problem, the posted text makes no sense.



Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

find the missing term between -5 and -2
Makes ABSOLUTELY NO SENSE!

No SEQUENCE/PATTERN can be established with just 2 numbers. There is no indication either, of the number of terms. 

If you really need help, then do the right thing!