O/L past papers › 2020
අ.පො.ස. (සා/පෙළ) ගණිතය 2020 ප්රශ්න පත්රය සහ පිළිතුරු
The G.C.E. O/L Mathematics 2020 paper (held March 2021 (cover shows no date; exam delayed by COVID-19)): all 42 questions from Paper I and Paper II, with what each question tests. Try any question free in Gedara Sir to check your answer and see step-by-step working in English and Sinhala.
VAT percentage from the tax added to a bill
Answer: 12%
💡 What it's asking: We want to know what percent Rs 180 is of Rs 1500, the bill before tax.
✅ 12% of 1500 = 180, so it matches.
රු. 1500 (බද්දට පෙර බිල) න් රු. 180 කොපමණ ප්රතිශතයක්ද යන්න සොයමු.
Base angle of an isosceles triangle from an exterior angle
Answer: x = 70
💡 What it's asking: Turn the outside angle into the inside angle, then use the equal base angles.
✅ Top angle = 180 − 70 − 70 = 40°, a sensible positive angle.
පිටත කෝණය ඇතුළත කෝණයට හරවා සමාන ආධාරක කෝණ යොදන්න.
Solve an equation with algebraic fractions
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