# Determine carers willingness to walk to access services

This question was posted the Coverage assessment forum area and has 3 replies. You can also reply via email – be sure to leave the subject unchanged.

### Franck Alé

Normal user

14 Feb 2013, 09:26

### Ernest Guevarra

Valid International

Technical expert

14 Feb 2013, 10:55

For example, if the scale of the map is 1:50,000, this means that for every 1cm in the map, it corresponds to 50,000 cms in actual distance. 50,000 cms is equal to 0.5 kms.

So, if two points are 20 cms apart when measured on the map, the actual distance in kilometres can be calculated as:

1 cm 20 cm

-------- = -------- ; x = 20 (0.5 km) = 10 kms

0.5 km x

So, the distance d between the two points is 10 kms.

There are other ways of calculating this distance depending on the geographic data that you have. For example, if you have GPS locations of points on the map, there are a lot of online applications that calculate these distances for you or you can apply simple coordinate geometry to get the difference between the two coordinates and come up with the distance.

I hope this answers your question.

### Mark Myatt

Frequent user

14 Feb 2013, 13:22

**adjacent**villages and towns with markets (these are the distances shown on the map). We take the mean "d" and divide by two to give an estimate at the largest distance that carers might be willing to walk to access services.

I hope this helps.