If a man walks to his office at ¾ of his usual rate, he reaches office 1/3 of an hour late than usual. What is his usual time to reach office?
Choose the most appropriate option
A) 2 hour	B) 5 hour	C) 1 hour	D) 3 hour	E) 2 hour

Rationale: c 1 hour speed ratio = 1 : 3 / 4 = 4 : 3 time ratio = 3 : 4 1 - - - - - - - - 1 / 3 3 - - - - - - - - - ? 1 hour
Answer: C