Table 1.

Difference between weighted and unweighted averages

Location (i)	Patients (w i)	Travel time (x i; minutes)
1	1	30
2	5	10
Calculations
Average travel time		$\frac{30+10}{2}=20min$
Weighted average travel time		$\frac{\left(1\times 30\right)+\left(5\times 10\right)}{1+5}=13.3min$