1. What does the first significant figure represent in each case
What does the first significant figure represent in each case? The first significant figure is also the most significant figure. It is the figure that has most impact on the size of the number, the digit with the highest value.

2. The least significant figure is also the last significant figure
The least significant figure is also the last significant figure. In decimal numbers, zeroes at the start of the number are not significant as they have no value. Zeroes at the end are considered significant.

3. Zeroes in the middle of significant digits are considered to be significant.

4. This means we identify the two most significant figures
This means we identify the two most significant figures..and look at which column the 2nd significant figure lies in. This is what we are going to round to. So in the first case, the 2nd most significant figure is 0, which is in the hundreds column. So we are going to round it to the nearest hundred. What is the nearest multiple of 100 to 2056? The answer is So we can see that we are rounding up because the 3rd significant figure is 5 or more, so it is more than half way between 2000 and 2100, so we round up.

5. s.f. is short for significant figures

6. Round to 1 significant figure
Round to 2 s.f.
Round to 3 s.f.
305 55
26.8
0.035
3064
25.98
0.1025
3.058
10568
0.1059
2.0048
1.995

7. Round to 1 significant figure
Round to 2 s.f.
Round to 3 s.f.
305
300 55 60
26.8 30
0.035
0.04
3064
3100
25.98 26
0.1025
0.10
3.058
3.1
10568
10600
0.1059
0.106
2.0048
2.01
1.995
2.00