r₁

n₁

r₂

n₂

r₃

n₃

r₄

n₄

Profit (£)

Offer

4

6

4

6

4

6

0 - 4

6

40.9416

15%

4

6

4

6

4

6

5

6

42.6443

20%

4

6

4

6

4

6

6

6

50.7725

20%