Simple interest

The Maths Habit

Would you rather have £100 today, or £10 a year for 12 years?

£10 a year is £120 in all, but you have to wait

Work out

  1. 1% of £400

    £4

  2. 3% of £400

    £12

  3. 5% of £200

    £10

  4. 2% of £650

    £13

Simple interest
The same amount of interest is added every year.

£800 at 3% simple interest for 4 years. Find the interest.

Year 1Year 2Year 3Year 4
£24£24£24£24
interest for one year
3% of £800 =£24
the same every year
£24×4=£96
Answer£96

£700 at 2% simple interest for 3 years. Find the interest.

Year 1Year 2Year 3
£14£14£14
interest for one year
2% of £700 =£14
the same every year
£14×3=£42
Answer£42

£800 at 3% simple interest for 4 years. Find the interest.

Year 1Year 2Year 3Year 4
£24£24£24£24
interest for one year
3% of £800 =£24
the same every year
£24×4=£96
Answer£96

£900 at 2.5% simple interest for 2 years. How much is it worth at the end?

Year 1Year 2
£22.50£22.50
interest for one year
2.5% of £900 =£22.50
the same every year
£22.50×2=£45
add it to the start
£900 +£45=£945
Answer£945

£800 at 3% simple interest for 4 years. Find the interest.

Year 1Year 2Year 3Year 4
£24£24£24£24
interest for one year
3% of £800 =£24
the same every year
£24×4=£96
Answer£96

£450 at 4% simple interest for 5 years. Find the interest.

Year 1Year 2Year 3Year 4Year 5
£18£18£18£18£18
interest for one year
4% of £450 =£18
the same every year
£18×5=£90
Answer£90

£800 at 3% simple interest for 4 years. Find the interest.

Year 1Year 2Year 3Year 4
£24£24£24£24
interest for one year
3% of £800 =£24
the same every year
£24×4=£96
Answer£96

£1600 at 3.5% simple interest for 2 years. How much is it worth at the end?

Year 1Year 2
£56£56
interest for one year
3.5% of £1600 =£56
the same every year
£56×2=£112
add it to the start
£1600 +£112=£1712
Answer£1712

£800 at 3% simple interest for 4 years. Find the interest.

Year 1Year 2Year 3Year 4
£24£24£24£24
interest for one year
3% of £800 =£24
the same every year
£24×4=£96
Answer£96

£350 at 6% simple interest for 2 years. Find the interest.

Year 1Year 2
£21£21
interest for one year
6% of £350 =£21
the same every year
£21×2=£42
Answer£42

Simple interest worksheet, page 1

Answer sheet

  1. £500 earns £60 simple interest in 4 years. Find the yearly rate.

    3%

  2. £300 is invested at 5% simple interest. How many years until it is worth £360?

    4 years

  1. £500 is invested at 4% simple interest a year for 3 years. Find the total interest.

    £60

  2. £1200 is invested at 2% simple interest a year for 5 years. How much is it worth at the end?

    £1320

  3. £400 earns £48 simple interest in 3 years. Find the yearly rate.

    4%
Exit tickets to print