Question

Find the amount and compound interest on 12800 for one year at 15/2% p.a compounded semi-annually

Answer 1

principal=12,800
rate of interest =15/2%×2=15%
time =1=2half years
so, amount =12,800×(1+r/100)²
= 12800×(1+15/100)²
= 12800×105/100×105/100
= Rs14,112
C. I =14112-12800=Rs1312

Answer 2

Given Principal P = 12800,n = 2 and R = 15/2 Semi annually = 15/4%.

We know that A = P(1+r/100)^n

                            = 12800(1 + (15/4)/100)^2

                            = 12800((400 + 15)/100)^2

                            = 12800(415/100)^2

                            = 13778.

We know that CI = A - P

                            = 13778 - 12800

                            = 978 rupees.


Hope this helps!