The area of a rectangular plot is 20 times its breadth. If the difference between the length and the breadth is 10 metres, what is its breadth? Pick one.
A) 10 metres
B) 5 metres
C) 7.5 metres
D) data inadequate
E) none of these

Rationale: "l × b = 20 × b ∴ l = 20 m and l – b = 10 ∴ b = 20 – 10 = 10 m answer a"
Answer: A