Question

What is the measurement 345.067 mg rounded to four significant digits?

Answer 1

significant digits start at the first nonzero number, so 345.067 to four digits is 345.1

The answer is A.

Answer 2

count four from the first digit to the fourth one. When you see the fourth one, look at the digit after. if it is 5+ then the fourth digit increases by one. if 5- then it stays the same. 6>5 so 0 becomes 1.

Therefore the answer is 345.1mg