Question

If the cost of $20$ books is $₹180$, then how much does $15$ books cost?

• A. $₹135$
• B. $₹95$
• C. $₹125$
• D. $₹160$

Answer 1

The correct option is A $₹135$

Let the required cost be $₹x$.
Here, the two quantities vary directly.
$\frac{20}{180}=\frac{15}{x}$
$20\times x=15\times 180$
$x=\frac{15\times 180}{20}$
$x=135$