3 shops sell TVs and all 3 are having sales. Here are the three original prices of the TVs and their discounts: X12: £150 (25%), Teli-vise: £235 (1/2 off), Xpert: £60 (with a year of weekly £8 payments). Which TV is the cheapest once discounted.
X12 = £150 x (1-0.25) = £112.50 Teli-vise: £235 / 2 = £117.50 Xpert: £60 + (12 x £8) = £156 Therefore the X12 is the cheapest television after the discount has been applied.