SOLUTION: How long will it take for the tip of the second hand to move 10 cm if its length is 7 cm? Round off your answer to the nearest hundredths.

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Question 1104868: How long will it take for the tip of the second hand to move 10 cm if its length is 7 cm? Round off your answer to the nearest hundredths.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
a complete revolution of the second hand takes 60 seconds.
the circumference of the circle that the tip of the second hand makes is equal to 2 * pi * 7 which is equal to 14 * pi centimeters.
14 * pi centimeters is equal to 43.98229715 centimeters.
the second hand does that in 60 seconds.
the second hand does 10 centimeters in 10/43.98229715 * 60 = 13.64185227 seconds.

to confirm, the circumference is equal to 43.98229715 centimeters.
10 centimeters divides into 43.98229715 centimeters 4.398229715 times.
multiply 13.64105227 seconds 4.398229715 times to get 60 seconds.

the solution appears reasonable.

it would take the second hand 13.64185227 seconds to move 10 centimeters.

round that to the nearest hundredth and your solution is 13.64 seconds.