The sum of money that yield a compound intrest of Rs.420 during the second years at at 5% p.a. is
1). Rs.4,000
2). Rs.42,000
3). Rs.8,000
4). Rs.21,000
Here is the right answer
A = P$ 1+\frac{R}{100} ^{T}$-1
420 = $\frac{41P}{400}-\frac{5P}{100}=\frac{21P}{400}$
P = $\frac{420\times 400}{21}$= 8000