Question 1
SEAMO self-study edition 2027; not an official 2027 paper. Original source years are retained. 25 questions, 90 minutes; Q1–10: 3 points, Q11–20: 4 points, Q21–25: 6 points, total 100. Original response types and all subparts are preserved. Verified is an editorial convention; source defects, necessary assumptions and unresolved mathematical uncertainty are disclosed.
Two circles have the same centre and different radii. The shaded region has area $25\text{ cm}^2$. Find the difference between the areas of the two circles, in $\text{cm}^2$. Take $\pi=3.14$.
Diagram interpretation: the horizontal and vertical radii are perpendicular, and the shaded region lies between the two chords joining their endpoints.
Two circles have the same centre and different radii. The shaded region has area $25\text{ cm}^2$. Find the difference between the areas of the two circles, in $\text{cm}^2$. Take $\pi=3.14$.
Diagram interpretation: the horizontal and vertical radii are perpendicular, and the shaded region lies between the two chords joining their endpoints.