Why similar fleets suffered unequal losses

Why did the French suffer far more casualties despite similar fleet sizes?

Their fleet was scattered and individual ships were often engaged by multiple concentrated British opponents, while French ships were also lost outright.

The disparity arose partly from the French ships lost outright and partly from the way the two fleets entered combat. Duff's weaker squadron drew the French into pursuit, stretching their formation just before Hawke arrived. The British maintained greater concentration and repeatedly brought two or more ships against an isolated French opponent. The casualty totals therefore reflect tactical geometry and fleet cohesion as much as the nominal similarity in ship numbers.