numbers it is significant. For example, 1.095 has four significant figures.
Zeros appearing at the end of a number.
(a) If a number contains a decimal point and the last number (digit) is a
zero, the zero is a significant figure. For example, 15.60 has four significant figures.
(b) If the last digit in the number is a zero and the number does not
contain a decimal point, the zero may or may not be significant. For example, the
number 1670 has four significant figures if the accuracy of the measurement included
the zero as a significant digit. If the digit seven was estimated, then the zero is not
significant and hence the number contains only three significant figures.
For all course work that follows, any trailing zeros will be considered
significant. For example, the number 1000 has four significant figures.
Number of significant
3 (for this subcourse)
1-28. IMPLIED LIMITS
If a laboratory result is reported as 3.6, it indicates that this value is accurate to
the nearest tenth and that the exact value lies between 3.55 and 3.65.
1-29. LABORATORY APPLICATION
The real importance of significant figures lies in their application to fundamental
a. Addition and Subtraction. When adding or subtracting, the last digit
retained in the sum or difference should correspond to the first doubtful decimal place of
the addends (least accurate number).
Example. Add 5.683 plus 0.0052.
Solution. In the number 5.683, the three is the doubtful decimal place; i.e.,
the value of this measurement could vary from 5.6825 to 5.6835. Since the fourth digit
after the decimal point is unknown, the answer is limited to four digits. Thus,
5.6882 ----> 5.688
b. Multiplication and Division. When multiplying or dividing, the product or