A sector has radius 14 cm and its arc is 11 cm long. Find the area of the sector in ${\text{cm}}^2$.

For any sector, area = ½ × arc × radius = ½ × $11\times 14=77{\text{cm}}^2$ — no value of π is needed. (Multiplying arc by radius without halving gives $154{\text{cm}}^2$; 39 cm is the sector's perimeter, 11 + 14 + 14, which is a length and not an area; $616{\text{cm}}^2$, taking π = 22/7, is the whole circle.)