How Many Significant Digits are in 0.0217

The number 0.0217 has 3 significant digits

Explanation:

Significant Digits

These are digits that contribute to the significance of the number. Some rules apply to discard the non-significant digits like:

Leading zeros Trailing zeros (with exceptions)

Our number is 0.0217 has two leading zeros before the 2 because they only occupy space to indicate the order of magnitude of the number. Only the 2,1,7 are significant digits, thus

The number 0.0217 has 3 significant digits