Which contain 3 significant figures and no others?

1. 326.0
2. 0.00310
3. 46,900
4. 1,070
5. 0.020

Isn't there more than one correct answer?
Thank You

I think numbers 1, 2, 3 and 4 all contain only 3 sig figs

2,3,4

number one contains 4 significant figures.

The question bothers me. What do they mean by "no others?"

#1 contains 4 s.f.
#2 contains 3 s.f. BUT it contains 3 zeros that are not s.f. which I see as "some others".
#3 contains who knows? Technically, with no decimal at 46900. it contains only 3 s.f. BUT it contains the two zeros that I read as "something other."
#4 has the same problem as #3. With no decimal after 1070. it counts as 3 s.f. for the 107 BUT it contains a zero which is "something other."
#5 contains 2 s.f. BUT it contains two zeros that are not significant which I read as something other.
Frankly, I think the problem needs work. As I read it NONE of them has 3 s.f. WITH NO OTHERS.

Yes, there is more than one correct answer. In order to identify which values contain 3 significant figures and no others, we need to understand the concept of significant figures.

The significant figures in a number are the digits that carry meaning in terms of precision. Some general rules for identifying significant figures are:

1. Non-zero digits are always significant. For example, in the number 326.0, all three digits (3, 2, and 6) are non-zero and therefore significant.

2. Any zeros between non-zero digits are significant. For example, in the number 0.00310, all three zeros between the non-zero digits 3 and 1 are significant.

3. Leading zeros (zeros to the left of the first non-zero digit) are not significant. For example, in the number 0.00310, the leading zeros before the 3 are not significant.

4. Trailing zeros (zeros to the right of the last non-zero digit) may or may not be significant. If the number contains a decimal point, the trailing zeros are significant. For example, in the number 326.0, the trailing zero is significant. However, if there is no decimal point, the trailing zeros may not be significant. For example, in the number 46,900, the trailing zeros may not be significant.

Using these rules, let's analyze each given value:

1. 326.0: This value has 3 significant figures (3, 2, and 6) and no other digits, so it meets the specified criteria.

2. 0.00310: This value has 3 significant figures (3, 1, and 0) and no other digits, so it also meets the specified criteria.

3. 46,900: This value has 2 significant figures (4 and 6), but the trailing zeros may or may not be significant depending on whether there is a decimal point. Since there is no decimal point provided, we cannot determine if the trailing zeros are significant or not.

4. 1,070: This value has 4 significant figures (1, 0, 7, and 0), so it does not meet the specified criteria.

5. 0.020: This value has 2 significant figures (2 and 0), so it does not meet the specified criteria.

Therefore, the correct answers are 1. 326.0 and 2. 0.00310, as they both contain 3 significant figures and no others.