dangling sentence?

[belltrio]

I wonder whether the following sentence is correct or not.
"Ten minutes suffice to train on the Segway, learning to maneuver it with ease." (from an ad.)
From my understanding, when two independent sentences are connected, a coordinator or subordinator must be used. If the above sentence is grammatically correct, please let me know why? and if incorrect, please let me know the correct sentence. Thank you very much!

[Raymott]

I wonder whether the following sentence is correct or not.
"Ten minutes suffice to train on the Segway, learning to maneuver it with ease." (from an ad.)
From my understanding, when two independent sentences are connected, a coordinator or subordinator must be used. If the above sentence is grammatically correct, please let me know why? and if incorrect, please let me know the correct sentence. Thank you very much!

I consider it incorrect. But the second clause can't be a free-standing sentence (it has no finite verb) so this isn't a run-on sentence.
"Ten minutes suffices to learn how to manoeuver the Segway with ease."

[BobK]

It's a lousy 'sentence'. It expects us to guess what the subject of 'learning' is.

b