This post relates to the George Facer kinetics answers for Q2 b,c and d, including the ‘e’ (explanation) points.
He is essentially discussing TWO factors that affect the rate of reaction when temp changes.
The proportion of molecules successfully colliding, with the correct orientation and E>= Ea
The number of collisions taking place.
He is saying (at least according to my interpretation!) that a 10oC drop in temperature will cause the rate to fall by 50% via factor #1, but factor #2 only causes a 2% fall due to the lower frequency of collisions at the lower temp.
So the factor that caused the 50% drop is far more significant and the 2% facto, hence factor #1 should always be the primary reason quoted for the change in rate at different temperatures.