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# The diagram shows an arc MN of a circle, centre O, with 10cm. If < MON = 72o....

### Question

The diagram shows an arc MN of a circle, centre O, with 10cm. If < MON = 72o. Calculate the length of the arc, correct to three significant figures. [Take $$\pi = \frac{22}{7}$$]

A) 6.28cm

B) 12.6cm

C) 22.6cm

D) 62.8cm

### Explanation:

Length of arc = $$\frac{\theta}{360 \times 2 \pi r}$$

= $$\frac{72}{360} \times 2 \times \frac{22}{7} \times 10$$cm

= 12.57

= 12.6cm(3 s.f)

## Dicussion (1)

• Length of arc = $$\frac{\theta}{360 \times 2 \pi r}$$

= $$\frac{72}{360} \times 2 \times \frac{22}{7} \times 10$$cm

= 12.57

= 12.6cm(3 s.f)