In this problem, we are asked to round off 70.427 into 3 significant numbers.
Recall that in determining the number of significant numbers, we following the following rules:
- All nonzero digits are significant.
- Zeroes between nonzero digits are significant.
- Zeroes to the left of the nonzero digits are not significant, their only purpose is to indicate placement.
- Zeroes to the right of the nonzero digits are categorized as follows:
- Trailing zeroes after a decimal point are significant.
- Trailing zeroes before the decimal point and after a nonzero digit are always significant.
- Trailing zeroes before an implied decimal point is ambiguous and should be avoided by using scientific notation.