The cost of 3 pens is Rs. 30, then the cost of 2 pens is Rs. 20.

The cost of 1 pen is Rs. 16 and the cost of 1 pencil is Rs. 5. What is the total cost of x pens and y pencils.

The cost of 1 pens is Rs 114 1/4 find the cost of 19 pens

The cost of 1 dozen pens is Rs. 24. Find the cost of 30 pens.

The cost of 24 pens is Rs 2986.80. Find the cost of one pen.