Question

Arjun wants to invest $Rs.15,000$ in two types of bonds. He earns $12\%$ in the first type and $15\%$ in the second. His investment in $15\%$ bond, if he has a total earning of $Rs.1,950$, is

• A. $Rs.10,000$
• B. $Rs.5,000$
• C. $Rs.6,000$
• D. $Rs.7,000$

Answer 1

The correct option is B $Rs.5,000$

Let Arjun's investment in $12\%$ bond be $x$ and in $15\%$ bond be $(15000-x)$

total earnings is $1950$

earning in $12\%$ bond is $=\frac{12}{100}\times x$

earning in $15\%$ bond is $=\frac{15}{100}\times (15000-x)$

As per problem,total earning$=1950$

$\Rightarrow (\frac{12}{100}\times x)+\frac{15}{100}\times (15000-x)=1950$

$\Rightarrow \frac{12x}{100}+\frac{225000-15x}{100}=1950$

$\Rightarrow \frac{12x+225000-15x}{100}=1950$

$\Rightarrow -3x+225000=195000$

$\Rightarrow -3x=-30000$

$\Rightarrow x=10000$

Therefore his investment in $15\%$ bond is $(15000-10000)=Rs5000$