Instruction: Each problem consists of a question followed by two statements. Decide whether the data in the statements are sufficient to answer the question. Dipu (D) is 15 years older than his brother Enam (E). \((D = E + 15)\). How old is Dipu? (1) Twenty years ago, Dipu's age was twice that of Enam. (2) Ten years later, Enam's age will be \(\frac{3}{4}\) (assuming the symbol is a typo for a fraction like \(\frac{3}{4}\) or the solution is based on the logic of sufficiency) that of Dipu.

Explanation: (D) Given \(D = E + 15\). (1) 20 years ago: \(D - 20 = 2(E - 20)\). Substitute E = D - 15: \(D - 20 = 2(D - 15 - 20) \implies D - 20 = 2D - 70 \implies D = 50\). (1) alone is sufficient. (2) 10 years later: \(E + 10 = \frac{3}{4}(D + 10)\) (assuming the typo means \(\frac{3}{4}\)). Substitute E = D - 15: \((D - 15) + 10 = \frac{3}{4}(D + 10) \implies D - 5 = \frac{3}{4}D + \frac{15}{2} \implies \frac{1}{4}D = \frac{10+15}{2} = \frac{25}{2} \implies D = 50\). (2) alone is sufficient (assuming a ratio can be formed). Therefore, each statement alone is sufficient.