what is 30% off of £51.85

$${\mathtt{5\,185}}{\mathtt{\,\times\,}}{\mathtt{0.7}} = {\frac{{\mathtt{7\,259}}}{{\mathtt{2}}}} = {\mathtt{3\,629.5}}$$

£34.29

Good work MG :))

(I think you mean 36.29 pounds)