Percentages (age 12+)
Solve problems involving percentage increase, percentage decrease, finding the original value after a percentage change, and calculating simple interest
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“If a bike originally costs £250 and its price goes up by 8%, can your child work out the new price — and if a savings account earns 3% simple interest per year, how much interest would £500 earn in 4 years?”
Full guide and materials
- Activity. Solve problems involving percentage increase, percentage decrease, finding the original value after a percentage change, and calculating simple interest
What to notice. Calculate a 15% increase on £240 using a decimal multiplier (× 1.15) • Find the original price before a 20% discount resulted in a sale price of £64 • Calculate simple interest on £500 at 3% per annum for 4 years
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If a bike originally costs £250 and its price goes up by 8%, can your child work out the new price — and if a savings account earns 3% simple interest per year, how much interest would £500 earn in 4 years?
Solve problems involving percentage increase, percentage decrease, finding the original value after a percentage change, and calculating simple interest
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Check understanding
- Calculate a 15% increase on £240 using a decimal multiplier (× 1.15)
- Find the original price before a 20% discount resulted in a sale price of £64
- Calculate simple interest on £500 at 3% per annum for 4 years
“If a bike originally costs £250 and its price goes up by 8%, can your child work out the new price — and if a savings account earns 3% simple interest per year, how much interest would £500 earn in 4 years?”
Curriculum record
- Type
- Procedural
- Subject
- Mathematics
- Domain
- Ratio & Proportion
- Age range
- Ages 12–14
Standards