Question

The cost of $1dozen$ gel pens is $₹144$ and the cost of $9$ ball pens is $₹81$. Find the ratio of the cost of a gel pen to the cost of a ball pen.

Answer 1

Step 1: Find the cost of a gel pen

$1dozen=12$

Cost of $12$ gel pens is $₹144$

Cost of $1$ gel pens is $₹\frac{144}{12}=₹12$

Step 2: Find the cost of a ball pen

Cost of $9$ ball pens is $₹144$

Cost of $1$ ball pens is $₹\frac{81}{9}=₹9$

Step 3: Find the ratio

ratio of the cost of a gel pen to the cost of a ball pen = $\frac{12}{9}=\frac{12÷3}{9÷3}=\frac{4}{3}=4:3$

Hence, ratio of the cost of a gel pen to the cost of a ball pen is $4:3$.