significant digit? need help!?

Question

It says determine the significant digits in following numbers

a) 220.22

so the significant digit would be 2 right? because the decimal moved 2 past 2 digits

What would be the significan digit for this problem?

b. 6,423
c. 3,4300

Answer 1

I find the set of guidelines below invaluable in deciding on significant figures:

The rules for identifying significant digits when writing or interpreting numbers are as follows:



All non-zero digits are considered significant. Example: 1, 20, and 300 all have one significant figure. They are 1, 2, and 3 respectively. 123.45 has five significant figures: 1, 2, 3, 4 and 5.

Zeros appearing anywhere between two non-zero digits are significant. Example: 101.12 has five significant figures: 1, 0, 1, 1 and 2.

Leading zeros are not significant. For example, 0.00012 has two significant figures: 1 and 2.

Trailing zeros in a number containing a decimal point are significant. For example, 12.2300 has six significant figures: 1, 2, 2, 3, 0 and 0. The number 0.000122300 still has only six significant figures (the zeros before the 1 are not significant). In addition, 120.00 has five significant figures. This convention clarifies the precision of such numbers; for example, if a result accurate to four decimal places is given as 12.23 then it might be understood that only two decimal places of accuracy are available. Stating the result as 12.2300 makes clear that it is accurate to four decimal places.

The significance of trailing zeros in a number not containing a decimal point can be ambiguous. For example, it may not always be clear if a number like 1300 is accurate to the nearest unit (and just happens coincidentally to be an exact multiple of a hundred) or if it is only shown to the nearest hundred due to rounding or uncertainty. Various conventions exist to address this issue:

A bar may be placed over the last significant digit; any trailing zeros following this are insignificant. For example, has three significant figures (and hence indicates that the number is accurate to the nearest ten).

The last significant figure of a number may be underlined; for example, "20000" has two significant figures. (sorry I canot enter a line under the first )

A decimal point may be placed after the number; for example "100." indicates specifically that three significant figures are meant.

However, these conventions are not universally used, and it is often necessary to determine from context whether such trailing zeros are intended to be significant. If all else fails, the level of rounding can be specified explicitly. The abbreviation s.f. is sometimes used, for example "20 000 to 2 s.f." or "20 000 (2 sf)". Alternatively, the uncertainty can be stated separately and explicitly, as in 20 000 ± 1%, so that significant-figures rules do not apply.

A number with all zero digits (e.g. 0.000) has no significant digits, because the uncertainty is larger than the actual measurement.



For the numbers you have given:



220.22 has 5 significant figures.



6423 has 4 significant figures



34300 has 3 sgnificant figures. (but as you read from the text, this is not certain)

Answer 2

our book should say what a significant digit is...so check this, but im pretty sure significant digits are ANY numbers that are:

1) not zero

2) between two significant numbers

3) zeros to the right of the decimal





so for a & b. all the numbers are significant

and c. has three significant numbers, 3, 4, 3.

Answer 3

no, it should be 5 significant figures for a), and for:

b) 4 significant figures...

c) 3 significant figures...



I have a technique for you.



If the decimal point is PRESENT, count the numbers starting from the non-zero digit up to the last digit of the given number from LEFT TO RIGHT. (example is: a. 220.22, since the decimal point is present, count from the non-zero digit in the left side, which is 2.. up to the last digit which is 2.. you will get 5 significant figures.)



However, if the decimal point is ABSENT, count numbers starting from the non-zero digit up to the last digit of the given number from RIGHT TO LEFT. (examples are: b. 6,423, it has no decimal point so count from right to left, starting from the non-zero digit, which is 3. Count the digits until you reach the last one, which is 6.. you will arrive at 4 significant figures.... for b. 34,300, you need to start counting from the non-zero digit in the right side, which is 3. Count the number of digits until you reach the end of the number. So you will get 3 significant figures.)



I hope you get it right.

Answer 4

that's 3 in the two a form of. The 0 is barely considerable regardless of if that's after yet another selection or decimal. as an occasion, 0.02 might in basic terms be 2 sig figs as a results of fact the 0 on the front isn't considerable.