There was one test (I can't remember which, but one of the ones I did (maybe M&R, but I could be mistaken - I took the test a couple weeks back, so it could have been multiple ones), my answers were slightly off - a rounding error, either in the working or in the final answer. It was untimed, so I did them multiple times, getting the same answer (I got good maths grades at GCSE, A-level and Uni modules). In the end, I realised it was a small mistake in the answers (most people would have just clicked through, for some reason, I was stubborn, trying to get the exact answer). But it definitely was a mistake on their end, which I find ironic for a law firm.