Explanation:

The number of members of sports club A, who did not participate in the event = (100 – 65)% of 4000 = 35% of the 4000 = 1400

The number of members of sports club D, who did not participate in the event = (100 – 30)% of 5000 = 70% of the 5000 = 3500

Hence, the required percent = (3500-1400)/3500 × 100 = 60%.