This exam tips covers Common Mistakes to Avoid within Integers & Decimals for GCSE Mathematics. Revise Integers & Decimals in Number for GCSE Mathematics with 14 exam-style questions and 22 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 11 of 13 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Common Mistakes to Avoid
❌ Wrong: 3.4 + 2.56 = 5.10
✅ Right: 3.4 + 2.56 = 5.96
Always align decimal points when adding
❌ Wrong: 0.5 × 0.2 = 1.0
✅ Right: 0.5 × 0.2 = 0.1
Decimal × decimal usually gives smaller answer
❌ Wrong: 4 ÷ 0.5 = 2
✅ Right: 4 ÷ 0.5 = 8
Dividing by decimal less than 1 gives larger answer
Practice questions for Integers & Decimals
What is the value of the digit 4 in the number 12.345?
Explain how to multiply two decimal numbers without a calculator.
Quick recall flashcards
Money calculation
£4.25 + £12.30 + £8.75
Line up decimals:
4.25
12.30
+ 8.75
------
25.30
Answer: £25.30
What is a decimal?
A number with a decimal point showing parts of a whole. The digits after the point represent tenths, hundredths, thousandths, etc.