In a certain city only two cellular (mobile) phone services are available. One is Radiance and other is DSML. It is known that `25%` of the city population uses the services of Radiance and `20%` uses the services of DSML. while `8%` uses both Radiance and DSML. It is also known that `30%` of those who uses Radiance services but not services of DSML have prepaid cards and `40%` of those who uses DSML .but not Radiance have prepaid cards while`50%` of those who uses the services of both Radiance and DSML have prepaid cards. What percentage of the population have prepaid cards?

Options

A. `12.5%`
B. `10%`
C. `13.9%`
D. `20%`

Answer

`=13.9%`