See the pattern here
£2.40 £3.05
£4.60 £7.90
£10.70 £13.00
£4.25 £8.50
£6.70 £8.50
£2.75 £3.55
£2.35
£1.90 £2.50
£5.90 £7.50
£5.50 £6.50
£6.50
£5.50 £8.90
£9.90
£6.10 £7.50
£3.35 £4.35
£3.40 £4.95
£1.85 £2.35
£2.50