What is the estimate of 779?

Answer 1

The front end estimate is 800. 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 779 to 1 trillion, I would estimate it as 0.
If I had to add 779 to 0.0000000001, I would use the number as given, or possibly the front end estimate. If I had to divide it by 7, I would estimate it as 770, because 770/7= 110. If I had to divide it by 10, I would estimate it as 780, because 780/10 = 78.

Answer 2

To the nearest ten, 780