Estimate 537+ 281 by rounding to the nearest ten.
When we round 537 to the nearest ten, we get 540.
When we round 281 to the nearest ten, we get 280.
So, if we add 540 and 280, we get 820.
When we round 281 to the nearest ten, we get 280.
So, if we add 540 and 280, we get 820.