"It is twenty-five past one."
Translation:Mae hi'n bum munud ar hugain wedi un.
pum is usual before nouns, not pump - this is explained in the course notes on 'Numbers', I think.
The hints for this sentences in the Time section do currently show ...bum munud... - if you are using the app you may need to get the latest version, as changes to the hints on the app can take a while to filter through the system.
- Mae hi'n bum munud ar hugain wedi un - it is twenty-five minutes past one
- Mae hi'n bump ar hugain wedi un - it is twenty-five past one (no 'minutes', so no noun immediately following ...'n bump)