(3) The age to be taken for the purpose of determining the amount payable to a disabled person is his age on the date specified in regulation 3(2) or 3(3) or, in the case of a disabled person to whom regulation 6 applies (Payment where pneumoconiosis is accompanied by tuberculosis) his age on the date specified in paragraph (1) of that regulation. With a view to determining the amount payable to a dependant of a disabled person under regulation 4(1), the age to be taken for the purpose of calculating the sum to be deducted from the amount which would have been payable to the disabled person had he still been alive is the age of the deceased at his last birthday preceding his death.