What is the estimate of 6560?

Answer 1

The front end estimate is 7000. But estimating a single number, in isolation and without context, is a complete waste of time. It all comes down to the context of what needs to be done with the number.

If I had to add 6560 to 1 trillion, I would estimate it as 0.
If I had to add 6560 to 0.0000000001, I would use the number as given, or possibly the front end estimate. If I had to divide it by 30, I would estimate it as 6570, because 6570/30 = 219. If I had to divide it by 11, I would estimate it as 6600, because 6600/11 = 600.

Answer 2

To the nearest hundred, 6600