UPSC CDS Math Area and Perimeter Questions

In a room whose floor is a square of side 10 m, an equilateral triangular table of side 2 m is placed. Four book-shelves of size 4m x lm x 9m are also placed in the room. If half of the rest of the area in the room is to be carpeted at the rate of ₹ 100 per square metre, what is the cost of carpeting (approximately) ?