A notebook costs ₹12 more than a pen. Three notebooks and two pens together cost ₹186. What is the price of one notebook?

Explanation

1. 01

   Let a pen cost ₹$p$. A notebook costs ₹$(p + 12)$.

2. 02

   $3(p + 12) + 2p = 186$, so $5p + 36 = 186$ and $p = 30$.

3. 03

   A notebook costs $30 + 12 = 42$, i.e. ₹42.