Sub-topic 1
2024 · National One-Eighth
Free
Riddles identifying the segment, sector, chord, diameter, arc and circumference
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Sub-topic 2
2024 · National One-Eighth
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Arc of $30^\circ$ at the centre of a circle of radius $1$ cm (true/false)
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Sub-topic 3
2026 · National Preliminary
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Distance from the centre to a chord of $18$ cm in a circle of radius $12$ cm
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Sub-topic 4
2025 · National Quarterfinal
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Shortest distance from $p$ to a circle of radius $10$ cm with a tangent of $24$ cm
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Sub-topic 5
2024 · National Final
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Radius of a circle with a $30$ cm chord at distance $8$ cm from the centre
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Sub-topic 6
2023 · National Preliminary
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Length of a chord for radius $15$ cm, $13$ cm and $17$ cm at given distances
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Sub-topic 7
2025 · National Quarterfinal
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Radius from a chord of $30$ cm at distance $8$ cm from the centre
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Sub-topic 8
2023 · National One-Eighth
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Intersecting chords: $ae\times be=ce\times de$ with $ae=20$, $be=9$, $de=30$
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Sub-topic 9
2021 · National Preliminary
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Riddle: the tangent, a secant meeting a circle at one point
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Sub-topic 10
2024 · National One-Eighth
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Arc of $30^\circ$ at the centre of a circle of radius $2$ cm (true/false)
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Sub-topic 11
2024 · National Preliminary
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Sector area and arc length with $\theta$ in degrees (true/false)
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Sub-topic 12
2023 · National Preliminary
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Riddle: $\pi$, the ratio of circumference to diameter
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Sub-topic 13
2003 · National Semifinal
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Sector area $\dfrac{1}{2}r^2\theta$ for $\theta$ in radians (true/false)
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Sub-topic 14
2003 · National Semifinal
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Arc length $r\theta$ for $\theta$ in radians (true/false)
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Sub-topic 15
2013 · National Preliminary
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Ratio of the areas of circles of radius $7$ cm and $14$ cm
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Sub-topic 16
2013 · National Preliminary
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Area of a circle in terms of the diameter, $\dfrac{\pi d^2}{4}$ (true/false)
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Sub-topic 17
2021 · National Preliminary
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Surface area of a spherical ball of circumference $0.70$ m, $a=\dfrac{c^2}{\pi}$
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Sub-topic 18
2022 · National Preliminary
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A sector is not part of the boundary curve of a circle (true/false)
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Sub-topic 19
2022 · National Preliminary
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A radius is not part of the boundary curve of a circle (true/false)
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Sub-topic 20
2022 · National Preliminary
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The centre is not part of the boundary curve of a circle (true/false)
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Sub-topic 21
2022 · National One-Eighth
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The centroid is not the centre of the circumcircle of a triangle (true/false)
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Sub-topic 22
2022 · National One-Eighth
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The circumcentre is the centre of the circumcircle of a triangle (true/false)
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Sub-topic 23
2023 · National Preliminary
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Chord length $l=2\sqrt{r^2-d^2}$ for radius $15$ cm and distance $12$ cm
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