ECZ 2020 · O-Level Paper 1 — Approximations

Chiyalwa estimated the length of a string as 15 cm. The true length of the string was 14.6 cm. Find the relative error in Chiyalwa's estimate.

Verified working — step 1

Relative error compares the size of the mistake with the TRUE length, so build the mistake first.

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

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