← GCSE Mathematics

N14 Estimation and rounding

Currently Secure · last touched 2026-10-20

Loose end of 14 Oct closed (circle-the-estimate, 1 mark, rounded first). Examready on a 2-mark 'Estimate' with 1 s.f. rounding shown, inside a timed section (7 Oct: worked exactly, 0/2).

Every change

WhenChangeEvidenceSession
2026-10-20Secure → Secureadjudicated paper #9 Q2: 1/1, why:loose, rounded first (79÷0.4) inside a timed section — the loose end 'one estimate inside the next timed section' is closed. No move: the spaced re-test would allow examready, but the 7 Oct timed 2-mark 'Estimate … show your working' scored 0/2 a week earlier, so examready waits on that shape.standalone
2026-10-14Secure → Securepaper #9 Q2: 1/1, loss=none — rounded to 79÷0.4 and picked 200 inside a timed section; 3 min on a 1-min guidesession 104
2026-10-08Secure → Secure8 Oct, cold and untimed, non-calc, fresh item: estimate (38.7 x 5.2) / 0.49 with the numbers used asked for. Wrote 40*5 = 200, 200/0.5 = 400: rounded first, 1/1 unaided. On the 7 Oct timed paper an estimate was worked exactly for 18 min.session 88
2026-10-07Secure → SecureExam practice 7 Oct (test #7, attempt #15, timed, no calculator) Q3: an 'estimate' item worked as an exact product by partitioning, no rounding, 18 min on focus against a 2 min guide, answer line 'skip'; 0/2. Marking only: no status change, for adjudication. Retrieval outcome: incorrect.standalone

In papers

AttemptPaperQMarksNote
Exam practice — week 42 · maths, lit, cs — GCSE Mathematics sectionexam-skills #921/1B1 200 chosen. Working 79/0.4 = 197.5 — rounded sensibly and picked the estimate. 3 min on a 1-min question.
Exam practice — week 41 — GCSE Mathematics sectionexam-skills #730/2M0: no rounding to 1 s.f. seen (9, 4, 0.5 required). Working is an attempt at the exact product by partitioning ('8*3=24, 0.72*100=72, 0.9*100=90, 72*90=6300+180=6480, 6480/100=64.8, 24*68.8=92.8, 92.8/0.48') with arithmetic errors; never reaches a value. A0: answer line 'skip'. 18 min on focus against a 2 min guide — the paper's time hog. Command word 'Estimate' not acted on.