A certain sum on simple interest becomes Rs. 49600 in 3 years and Rs. 56000 in 5 years. If the rate of interest had been 2% more, then in how many years sum had been tripled?
Answer & explanation
Correct answer: option 2
56000 - 49600 = 6400
SI = \(\frac{6400}{2}\) = 3200
3SI = 9600
P = A - (SI of 3 years)
P = 49600 - 9600 = 40000
R = \(\frac{3200 }{40000}\) × 100% = 8%
Now,
A= 3P = P + 2P (SI)
Increased rate = 10%
SI = PRT
2P = \(\frac{P × 10 × T }{100}\)
T = 20 years