On 01 June 2022, Denny Dan, an attorney carrying on business in the Republic, entered into a two- year instalment sale agreement for the purchase of a personal computer. An instalment of R450 was payable each month. Had he purchased the personal computer for cash, he would have paid R9 000. Interest of R952 is incurred in terms of section 24 during his 2023 year of assessment. The personal computer was delivered to his offices on 01 June 2022 and immediately brought into use. A three- year write-off period on personal computers is allowed for income tax purposes. Denny Dan's practice is not registered for VAT. 

What amount will Denny use when calculating the wear and tear allowance for the 2023 year of assessment?