What is the next number? question

[gsingh2011]

"What is the next number?" question

I saw this question online but an answer wasn't provided. I've thought about it for a long time but I can't find an answer. Can anyone solve it?

What is the next number?
10, 13.33, 20, 26.66, 40, 46.66, 60, 66.66, 80, 100

 

[Bill Simpson]

Multiply by 3, Round off, Divide by 10, Subtract 1... and look carefully.

OR pick absolutely number you like and it is easy to come up with a formula that will have the ones given in order followed by the number you picked.

 

[gsingh2011]

Multiply by 3, Round off, Divide by 10, Subtract 1... and look carefully.

OR pick absolutely number you like and it is easy to come up with a formula that will have the ones given in order followed by the number you picked.

Wow, did you figure that out right now or have you seen it before?

I did the multiplying three thing myself, and I kind of found a pattern, but dividing by ten and subtracting one was genius.

 

[Bill Simpson]

I had never seen this before.

I stared at it for a couple of seconds, multiplied to get rid of the fractions, saw there was a trailing zero on every number, dropped those, stared at it for a couple of seconds and realized PRIMES!

But, as I said in my first reply, these "what is the next number" often aren't really "math."

 

[QuantumJG]

So the next answer is 106.66?

 

[gsingh2011]

So the next answer is 106.66?

That's what I got.