In one and a half hours, the minute hand of a clock rotates through an angle of
A
90o
B
180o
C
640o
D
450o
E
540o
Verified Correct Answer: E.
Step-by-Step Mathematical Solution
1 hr, = 60 mins, 60 mins = 360o
30 mins = \(\frac{360^o}{1}\) c \(\frac{30}{60}\)
= 180o
90 mins = 360 + 180o
= 540o
Source: Myschool Past Questions Archive (Record #32575)