Explanation:

- Successive discounts work by multiplying their complements. For example, a 5% discount gives you 95% of the price, so it's represented as 0.95.

- The formula for successive discounts is:

Final Price = (1 - D1) * (1 - D2) * (1 - D3) * Original Price.

- Given discounts are 5%, 10%, and p%, we calculate:

\( (1 - 0.05) \times (1 - 0.10) \times (1 - \frac{p}{100}) = (1 - 0.316) \).

- Simplify to get:

\( 0.95 \times 0.90 \times (1 - \frac{p}{100}) = 0.684 \).

- Solve for p:

\( 0.855 \times (1 - \frac{p}{100}) = 0.684 \)

\( (1 - \frac{p}{100}) = \frac{0.684}{0.855} \)

\( 1 - \frac{p}{100} = 0.8 \)

\( \frac{p}{100} = 0.2 \)

\( p = 20 \).

- Option:3, 20 is the correct value for p.

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