Question

Is the sequence –9.9, –13, –16, –19.2, … arithmetic? If so, identify the common difference.

Answer 1

What's the change between -9.9 and -13?

Answer 2

-22.9

Answer 3

no wait, its -3.1

Answer 4

does:

a1-a2 = a2 - a3 ?

or, a1+a3 = 2 a2

or, (a1+a3)/2 = a2?


if so, then its bound to be arithmetic

Answer 5

as is, i dont see how that 16+9.9 can half out to 13

Answer 6

A.

yes, –3.2

B.

yes, –2.9

C.

yes, –3.1

D.

no

Answer 7

@amistre64

Answer 8

do you see a way that (16+9.9)/2 = 13 ?? if not, then I know which one id pick