Answer :
Significant figures maintain precision in calculations. The number of significant figures in the result matches the least precision in the data values. Rounding follows specific rules depending on whether the digits are above, below, or exactly halfway to the next value.
Understanding Significant Figures and Rounding
The concept of significant figures is a way to express precision in measured and calculated numbers. When adding or subtracting, the result should be reported to the least number of decimal places found in any number in the series. For multiplication and division, the result should have as many significant figures as the number in the series that has the smallest amount of significant figures.
For example, when you calculate 56.0 + 3.44, you should end up with a result that has one decimal place, as 56.0 has the least number of decimal places, so the answer is 59.4. However, for multiplying 56.7 x 66.99, the product must be rounded to three significant figures because 56.7 has the least with three significant figures, thus the answer would be 3800 when rounded to three significant figures (though the exact product is 3799.733 before rounding).
Rounding rules are important when finalizing an answer. If the digit to the right of your rounding digit is 5 or higher, you round up. If it is less than 5, you do not round up. In some cases, when the number is exactly halfway, you would round to the nearest even number to maintain statistical consistency over time.