round-off error

To round off 430 you will have to round up or down. To round down then it till be 400 to round up it will be 500

Round off to the nearest cent, means round off to the nearest hundredths or round off to two decimal.

When you round off the number 0.472 to the hundredths place you get 0.47. If you round it off to the tenths place, it would be 0.5.

Yes but, if you can, you should try to round one up and the other down. Unless that results in rounding well away from the number.

For example, 48*62

Exact answer = 2976

If you round 48 up to 50, 62 down to 60

Estimate = 50*60 = 3000 (estimation error = +0.8%)

But if you had 48*68

Exact answer = 3264

Round up and down: 50*60 = 3000 (estimation error = -8.1% )

Round down and up: 40*70 = 2800 (estimation error= -14.2%)

Round up and up: 50*70 = 3500 (estimation error = +7.2%)

The last still has a large error but it is the smallest of the these.