HKIMO 2026 Grade 7 National Preliminary Set 02 Question 17

Uncle An has a rectangular garden 9 m wide and 10 m long. He uses a corner for a pond as shown and grows vegetables in the rest. Find the vegetable area in $\mathrm{m}^2$. Take $\pi=22/7$.

Editorial interpretation of the drawing: the pond is a quarter-circle centered at the upper-left corner.