11 580
= 11 600 (to 3 sig.fig)
All the numbers in 11 580 are significant figures except 0, which can either be a significant figure or not when it is behind.
So for 3 significant figures, you will only keep the 1, 1 and 5. However, you will need to round up because there is a 8 behind the 5, so it becomes 11,600
