My son only took GCSE maths and went straight to maths and FM A-levels. He got an A* on maths last year, and is predicated A* for FM, so it is possible without any additional further GCSE maths. He plans to study physics and took C 1,2,3,4,D1,M1,2,3 , FP1,2,3 and S1 - there is a small amount of stats in physics - looking at e.g. anomalies and lines of best fit, which he found useful.