Compound Interest

Paul leaves £4000 in the bank for two years. It earns compound interest of 5% per year. Calculate the total amount Paul has in the bank at the end of the two years.

• £410

• £4410

• £4200

• £200

The population of birds on an island is estimated to increase by 10% every year. The population of birds on the island is 20000. Calculate the population of the birds in three years time.

• 22000

• 20200

• 26620

• 18000

The value of a car decreases by 5% each year. Sophie bought a car two years ago for £10 000. Work out the value now.

• £5000

• £9000

• £9025

• £95 000

Sam invests £1800 in the bank for four years. It earns compound interest of 4% each year. Calculate the total amount Sam has in the bank at the end of the four years.

• £2105.75

• £2105.74

• £6914.88

• £2024.76

Carrie invests £800 for 4 years at 3% interest per year. How much interest does she earn?

• £74.18

• £100.40

• £100.41

• £96

The height of a sunflower increases by 60% each year. When planted, the sunflower was 40 cm tall. How tall will the sunflower be in 5 years time?

• 419.43 cm

• 53.52 cm

• 4.19 m

• 420 cm

A full water tank holds 500 litres. The tank begins to leak water and is losing 14% of its contents every hour. Find out how much water is left in the tank after 8 hours.

• 149.61 litres

• 350 litres

• 340 litres

• 149.6 litres

A house was bought for £100 000. Its value appreciates by 7.5% for the first two years. It then depreciates by 6% for the next 4 years. How much is the house worth now?

• £101 000

• £101 050

• £90225

• £86500

A tree is 80 cm when planted. Each year, the height of the tree increases by 22%. After how many complete years will the height of the tree be at least 3m?

• 8 years

• 7 years

• 10 years

• 9 years

Charlotte invests £5000. The bank pays 10% interest for the first year and then y% every year after that. After three years, Charlotte has £5610.55. Calculate y.

• 1%

• 2%

• 3%

• 1.5%