Given: The principal is 625 rupee Rate is 8% Concept: SI=(P×R×T)/10 0 CI=P[(1+r/100)n−1] Here, n is the number of terms in the year. Calculation: The simple interest for 2 years ⇒(625×8×2)/100 ⇒25×2×2 ⇒ 100 rupee Now, Compound interest for 2 years is ⇒625[(1+8/100)2−1] ⇒625[(108[100)2−1] ⇒625[(108)2−(100)2]×1/10000 ⇒(208×8)/16 ⇒ 104 rupee Now, The difference between CI and SI is ⇒104−100 ⇒ 4 ∴ The difference between CI and SI is 4. The difference between CI and SI for 2 years is P(r/100)2 The difference is ⇒625(8/100)2 ⇒625×4/625 ⇒ 4 ∴ The difference between CI and SI is 4. This short trick works only for 2 years.