ECZ 2018 · GCE Paper 1 — Similarity and Congruency

The ratio of the heights of two containers that are geometrically similar is 2 : 3. If the surface area of the smaller container is 80 cm2, find the surface area of the larger container.

  • A. 120 cm2
  • B. 270 cm2
  • C. 180 cm2
  • D. 360 cm2

Verified working — step 1

Heights are lengths, and similar solids scale AREA by the SQUARE of the length ratio - the cube is for volumes.

The full step-by-step working and final answer are included with Premium — checked against ECZ marking standards.

Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.

Have a different question?

Search it — if it is from a past paper or a school mock, chances are we have it worked out, or one that uses the same method.

Search any past-paper question

More Similarity and Congruency questions from past papers