I have a confusion regarding significant and rounding off data, What would be correct answer of this , if we add them: 5.00 + 0 .775 + 0.0001 = ??? What would be its correct answer??

1 Answer
May 26, 2016


The correct answer is 5.78


When you add the values 5.7751 is the total. Be sure to line up your decimals!
The first value 5.00 has 3 sig figs, last in the hundredths place.
The second value 0.775 also has 3 sig figs, the last in the thousandths place.
The third value 0.0001 has 1 sig fig but holds the ten thousandths place.

The rule is- circle the last significant digit farthest to the right in each value. Locate the sig fig farthest to the left and draw a line to the right of it. This is the last significant place.

Round to this place. 0.0051 rounds up 0.01, thus bumping 5.77 up to 5.78