When Kaya charges her phone, it gains 2 percentage points each minute.
When Kaya uses her phone, it loses 5 percentage points each minute.
Once, Kaya used her phone for some time, and then charged it for twice the
amount of time she used it. In the end, her phone lost 10 percentage points.
How long did Kaya use her phone and how long did she charge it?
Kaya used her phone for 20 minutes and charged it for 10 minutes
Kaya used her phone for 10 minutes and charged it for 20 minutes
Kaya used her phone for 30 minutes and charged it for 15 minutes
There is not enough information to solve