Question

Match the options:

If 3 dogs, 4 cats, 6 rats and 7 lions costs ₹5, ₹9, ₹11 and ₹13 respectively. Then,

• A. 21 lions
• B. 30 rats
• C. ₹30
• D. ₹36

Answer 1

Number of animals ∝ Price

If two quantities are direct proportional, then the ratio of the two quantities is constant i.e,

$\begin{array}{ccc}\text{Number of dogs}& \text{3}& \text{18}\\ Price& 5& ?\end{array}$
$\frac{3}{5}=\frac{18}{x}$
$x=18\times \frac{5}{3}$
$x=₹30$

Similarily , we have

$\begin{array}{ccc}\text{Number of cats}& \text{4}& \text{16}\\ Price& 9& 36\end{array}$

$\begin{array}{ccc}\text{Number of rats}& \text{6}& \text{30}\\ Price& 11& 55\end{array}$

$\begin{array}{ccc}\text{Number of lions}& \text{7}& \text{21}\\ Price& 13& 39\end{array}$