The length of a rectangular floor is more than its breadth by 200%. If Rs.400 is required to paint the floor at the rate of Rs.3/sq m, what would be the length of the floor?
Options
A) 12
B) 18
C) 20
D) 22
E) 24

Rationale: "let the length and the breadth of the floor be l m and b m respectively . l = b + 200 % of b = l + 2 b = 3 b area of the floor = 400 / 3 = 133.33 sq m l b = 133.33 i . e . , l * l / 3 = 133.33 l ^ 2 = 400 > l = 20 . c"
Answer: C