উত্তর
ব্যাখ্যা
Given,Principal,P = tk. 1000
Compound rate,R = 20%per annum
= 20/2
= 10% half-yearly
Time = 18 month
= 3 half - years
Amount,A = {P × [1 + (R/100)]n}
= {1000 × [1 + (10/100)]3}
= (1000 × 11 × 11 × 11) ÷ (10 × 10 × 10)
A = tk.1331
Hence, compound interest = tk.1331