120 copies of a book cost Rs. 6000. What will be 400 copies cost?

120 copies of a book cost Rs. 6000. What will be 400 copies cost?

Explanation

Cost of 120 copies = Rs. 6000

Cost of 1 copy = Rs. 6000 / 120

= Rs. 50

Cost of 400 copies = Rs. 50 × 400

= Rs. 20000