Clocks Q

Chinn_asama wrote:Hi

I don't know if these kind of Qs are asked in GMAT, but they are asked in different admission tests. Here is the Q: At what angle the hands of a clock are inclined at 15 minutes past 5?

The answer is 67 1/2 degree. Can anyone explain, why?

Thanx

A clock has 60 divisions
Each division = 360/60 = 6 degrees

At 5 o clock, the angle between the hands is 25*6 = 150 degrees
At 5:15, the minutes hand has moved 90 degrees in a quarter of an hr
the hours hand will move a quarter of 6*5 degrees = 1/4 (30 degrees) = 15/2 degrees

Angle between the 2 hands = 150 - 90 + 15/2 = 60 + 7.5 = 67.5 degrees