Quantitative Aptitude Ques 2229
Question: At what rate will a sum of Rs. 1000 amount to Rs. 1102.50 in 2 yr at compound interest?
Options:
A) 6%
B) 6.5%
C) 5%
D) 5.5%
Show Answer
Answer:
Correct Answer: C
Solution:
- Given, $ P=Rs.1000, $ $ T=2yr, $ $ A=Rs\text{. 1102}\text{.50,} $ $ r=? $ We know that, $ A=P{{( 1+\frac{r}{100} )}^{T}} $
$ \Rightarrow $ $ 1102.50=1000{{( 1+\frac{r}{100} )}^{2}} $
$ \Rightarrow $ $ \frac{1102.50}{1000}={{( \frac{100+r}{100} )}^{2}} $
$ \Rightarrow $ $ \frac{11025}{10000}={{( \frac{100+r}{100} )}^{2}} $
$ \Rightarrow $ $ {{( \frac{105}{100} )}^{2}}={{( \frac{100+r}{100} )}^{2}} $
$ \Rightarrow $ $ \frac{105}{100}=\frac{100+r}{100} $
$ \Rightarrow $ $ 105=100+r $
$ \Rightarrow $ $ r=105-100=5 $ %
$ \therefore $ $ r=5 $ %
BETA
