Smarter people did better than Dumber people. The people with a score of 8,9 on numeracy did the best [1] but not as good as they should've. This is basically best shown on page 12 [2] on the actual paper, people with high numeracy have a better chance of correct answer than low numeracy.
I suspect the effect is even across low & high numeracy but because high numeracy people were more likely to get the correct answer to begin with. Akin to say you playing a toddler in Counter-Strike. You're more likely to win a round than them. So if for a round I disconnect one of your controllers then the disconnection is more likely to cause you a loss than the toddler because the toddler was going to lose anyways, the effect of disconnection for them is dwarfed by their innate ability.
[1]: https://youtu.be/zB_OApdxcno?t=413
[2]: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2319992