State the number of significant figures.
1) 809 Answer : 3
2) 0.0060 Answer : 5?
3) 0.00000095 Answer : 9?
4) 5.60 Answer : 3
5) 5.743 Answer : 4
6) 0.010 Answer : 4?
2, 3, 6 are wrong: Zeroes to the left of significant digits are NOT significant, unless they are between two non zero digits.
To determine the number of significant figures in a given number, follow these steps:
1) Non-zero digits (1-9) are always significant.
2) Any zeros between non-zero digits are significant.
3) Leading zeros (zeros to the left of the first non-zero digit) are not significant.
4) Trailing zeros (zeros to the right of the last non-zero digit) are significant if there is a decimal point present in the number.
Now, let's apply these rules to each number:
1) 809: There are 3 non-zero digits, so the answer is 3.
2) 0.0060: There are 2 non-zero digits (6 and 0) and 2 trailing zeros after the decimal point, so the answer is 4.
3) 0.00000095: There are 2 non-zero digits (9 and 5) and 7 trailing zeros after the decimal point, so the answer is 9.
4) 5.60: There are 3 non-zero digits (5, 6, and 0), and the zero between the non-zero digits is significant. The trailing zero after the decimal point is also significant, so the answer is 3.
5) 5.743: There are 4 non-zero digits (5, 7, 4, and 3), and the trailing zero after the decimal point is significant, so the answer is 5.
6) 0.010: There is only 1 non-zero digit (1) and 1 trailing zero after the decimal point, so the answer is 2.