Mathematics · Grades 5–8
Find the mistake: fractions and percentages · revision card
Equivalent fractions require multiplying or dividing numerator and denominator by the same nonzero number.
Keep these ideas clear
Preserve the value
Equivalent fractions require multiplying or dividing numerator and denominator by the same nonzero number.
Use the right whole
A percentage comparison changes when the reference whole changes.
Two useful examples
Correct 1/3 + 1/4 = 2/7 and explain.
Use a common denominator: 4/12 + 3/12 = 7/12. Adding denominators is not the addition rule.
Use a common denominator: 4/12 + 3/12 = 7/12. Adding denominators is not the addition rule.
A pupil writes 3/5 ÷ 2 = 6/5. Correct it.
3/5 ÷ 2 = 3/10; dividing by 2 multiplies by 1/2.
3/5 ÷ 2 = 3/10; dividing by 2 multiplies by 1/2.
Explain it without looking
- An item rises from 40 to 50 units. What is the percentage increase?
Learning preview · teacher review required. Grade bands are approximate, not official curriculum alignment.