40a (3)

yes as the expense has not increased Rs.20000/- per daily basis, but kindly take care that you will not get receipt of 45000/- at single receipt otherwise it get disallowed u/s 40a(3)

Either take 4 bills for less than 20000 on different days or though wrong  make payment in the name of different persons on a single day

CASH PAYMENT EXCEEDING  Rs. 20,000

Sec 40A(3) of Income tax Act, 1961

                                           Section 40A(3)(a) of the Income-tax Act, 1961 provides the at any expenditure incurred in respect of which payment is made in a sum exceeding Rs. 20,000/- otherwise than by an account payee cheque drawn on a bank or by an account payee bank draft, shall not be allowed as a deduction.

if payment is being made for plying, hiring or leasing goods carriages then Limit for these section is Rs. 35000/-,instead Of 20,000/- 

                              Section 40A (3) is an anti tax-evasion measure. By requiring payments to be made by an account payee instrument, it is possible to verify the genuineness of the transaction thereby mitigating the risk of evasion.

 Aggregate Payment has to be seen: After the amendment w.e.f 2009-10 if a person makes more than one different purchases for cash from same person in excess of Rs 20,000 in a single day even though on separate cash memos, such aggregate payment will be disallowed u/s 40A(3)

The Supreme Court in the case of Attar Singh Gurumukh Singh V ITO 1991  191 ITR 667 has held that the disallowance under section 40A (3) covers all outgoings including purchase of stock in trade.