Explanation:

To find the single discount equivalent to successive discounts, multiply the complements of the discounts and subtract from 1:

- Start with 100%:

- First, apply the 20% discount:

- 100% - 20% = 80% (or 0.8 in decimal form)

- Second, apply the 35% discount:

- 80% of 100% becomes 65%: \(0.8 \times (1 - 0.35) = 0.8 \times 0.65 = 0.52\)

- Finally, apply the 10% discount:

- 52% becomes 90% of it: \(0.52 \times (1 - 0.1) = 0.52 \times 0.9 = 0.468\)

- The combined effect is a single discount equivalent to 1 - 0.468 = 0.532, or 53.2%

- Therefore, Option 1: 53.2% is the correct answer.