How many significant digits in the number 0.00512

There are three significant digits in the number 0.00512.

How many significant digits in the number 3200

There are four significant digits in the number 3200.

How many significant digits in the number 300

There are only one significant digit in the number 300.

How many significant digits in the number 135.210

There are six significant digits in the number 135.210.

Round to 3 significant digits: 3.45991 x 106

The number 3.45991 x 10^6, rounded to 3 significant digits, is 3.46 x 10^6.

Round to 2 significant digits: 0.0034600