Question

What is the rate of simple interest per annum?
(I) The sum triples in 20 years at simple interest.
(II) The difference between the sum and the simple interest earned after 10 years is Rs. 1000.

• A. Statement (I) alone is sufficient, but statement (II) alone is not sufficient.
• B. Statement (II) alone is sufficient, but statement (I) alone is not sufficient.
• C. Both statements together are sufficient, but neither statement alone is sufficient.
• D. Each statement alone is sufficient.

Answer 1

The correct option is A Statement (I) alone is sufficient, but statement (II) alone is not sufficient.

$\because I=\frac{P\times R\times T}{100}$ and Amount $=P+I$
(I) $\Rightarrow Amount=3P=P+I\Rightarrow I=2P$
$\therefore R=\frac{I\times 100}{P\times T}=\frac{2P\times 100}{P\times 20}=$10%
(II) $\Rightarrow P-I=1000$; here neither the sum nor interest is given.
$\therefore$ Hence, only statement I alone is sufficient.