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Circles, SM-Bank 036 MC

A yoyo at the end of a string moves through a quarter circle arc, as shown below.

The string is 70 cm long.
 

 
The curved distance the yoyo has travelled is closest to

  1. \(80\ \text{cm}\)
  2. \(90\ \text{cm}\)
  3. \(100\ \text{cm}\)
  4. \(110\ \text{cm}\)
Show Answers Only

\(D\)

Show Worked Solution
\(\text{Distance}\) \(=\dfrac{1}{4}\times 2\pi r\)
  \(=\dfrac{1}{4}\times 2\pi 70\)
  \(= 109.9557\dots\)
  \(\approx 110\ \text{cm}\)

\(\Rightarrow D\)