Let the cost price of the item be \( C \).
Step 1: When the item is sold at a 20% discount, the selling price is \( 0.8 \times \text{marked price} \). The profit is given as 20%. So, the selling price is \( C + 0.2C = 1.2C \).
Thus, the marked price \( M \) is:
\[
0.8M = 1.2C \quad \Rightarrow \quad M = \frac{1.2C}{0.8} = 1.5C.
\]
Hence, the marked price is \( 1.5C \).
Step 2: Now, when the item is sold at a 10% discount, the selling price is \( 0.9 \times M = 0.9 \times 1.5C = 1.35C \).
Step 3: The profit in this case is:
\[
\text{Profit} = 1.35C - C = 0.35C.
\]
Thus, the profit percentage is:
\[
\text{Profit Percentage} = \frac{0.35C}{C} \times 100 = 35%.
\]