PRIMARY 5 · MATHEMATICS

Decimals
Top 5 mistakes

Ranked by how often they appear across 40 MOE-aligned practice questions in our archive.

#1Calculation error

Divided by 100 instead of 1000.

Seen in 1 question

#2Calculation error

Divided by 10000 instead of 1000.

Seen in 1 question

#3Misconception

Divided by 10 instead of 1000.

Seen in 1 question

#4Misconception

Changed only the unit label without performing either conversion, leaving the number unchanged at 4.85.

Seen in 1 question

#5Calculation error

Correctly converted to mm (48.5 mm) but then divided by 100 instead of 1 000: 48.5 ÷ 100 = 0.485 m, confusing the mm-to-m factor with the cm-to-m factor.

Seen in 1 question

Want to fix these mistakes for your child?

Superholic Lab's quiz engine flags every misconception by name and routes your child to targeted practice in our 3-day Plan Quest. Free 7-day trial.

Start a free 7-day trial →