If the tax on the transaction is assumed to be £1,000,000, the amount of tax relief will be £1,000,000 x (0.7 x 0.8) = £560,000, leaving the taxpayer to pay £440,000.
Os tybir mai £1,000,000 yw’r dreth ar y trafodiad, swm y rhyddhad treth fydd £1,000,000 x (0.7 x 0.8) = £560,000, a bydd £440,000 ar ôl i’r trethdalwr ei thalu.