A student performs a titration with different burettes and finds titre values of 25.2 ml, 25.25 ml and 25.0 ml. The number of significant figures in the average titre value is:

We have 25.20, 25.25 and 25.00 ml.
Average = (25.20 + 25.25 + 25.00) / 3 = 75.45 / 3 = 25.15 = 25.2
In case of division, the final answer will contain as many significant figures as there are in the number with the least significant figures. So, the significant number is 3.