Download Dividing with Significant Figures

Dividing with Significant Figures
• In calculations, the accuracy of the calculated
result is limited by the least accurate
measurement involved in the calculation.
• Division
▫ After dividing the numbers, you then round the
result off so it has the same number of significant
figures as the component with the smallest
number of significant figures.
 12.60 / 3.0 = 4.2  4.2
(4 s.f.)
(2 s.f.)
(2 significant figures)
 4.840 – 4.30 = 1.12558  1.13
(4)
(3)
(3)
Rules for Rounding
1.
▫
2.
▫
3.
1.
If the digit to be dropped is more than 5, the digit just to the left
of it goes up by 1.
12.6  13
If the digit to be dropped is less than 5, the digit just to the left
stays the same.
12.4  12
If the digit to be dropped equals 5 and
The number after it is not a zero, then the digit just to the left goes
up by l.
12.51  13

2.
1.
The number after it is a zero, then
If the number to the left is odd, round up.

2.
11.5  12
If the number to the left is even, round down.

12.5  12