How long is the minute hand on a clock whose tip travels 15 cm from 1:15 to 1:30 to the nearest tenth?
The complete circumference is 2*pi*r where r is the length of the minute hand.
One quarter of the circumference equals 15 cm so:
2*pi*r/4 = 15
r = 2*15/pi so r = 9.5 cm to 1dp
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+120 
