Transcript 07 Significant Figures

Mathematics
Significant
Figures
Stage 6 - Year 11
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1
Significant Figures
•All non-zero numbers are significant
2971
32.5
7.456
•zeros between non-zero digits are significant
3071
60.5
8.009
•zeros at the end of a decimal are significant
297.10
32.00
9.000
Practice
•all other zeros are not significant.
0900
0254
0.456
2
Significant Figures
Write 354 567 to 3 significant figures.
1. The first significant figure is the first non-zero
number from the left (underlined in red).
2. Underline the next 2 digits.
The answer is 354 000, but
3. Looking at the next digit, underlined in blue.
(Use 5/4 rounding to find the correct 3rd digit.)
4. Since the 4th digit is 5 or greater, round up.
The answer is 355 000.
3
Significant Figures
Write 0.077 356 to 2 significant figures.
1. The first significant figure is the first non-zero
number from the left (underlined in red).
2. Underline the next digit.
The answer is 0.077, but
3. Looking at the next digit, underlined in blue.
(Use 5/4 rounding to find the correct 3rd digit.)
4. Since the next digit is 5 or less, round down.
The answer is 0.077.
4
Significant Figures
2.340
1
2
3
4
5
5
Significant Figures
0.040
1
2
3
4
5
6
Significant Figures
2340
1
2
3
4
5
7
Significant Figures
120.34
1
2
3
4
5
8
Significant Figures
2020
1
2
3
4
5
9