A company is considering implementing a lockbox system. There is an annual fee of $5,400 plus a transaction fee of $0.05 per payment. The average size of customer payments is $2,680, and there are 22 payments made daily on average. The company can earn an EAR of 2.28% on its cash balances. For the lockbox system to be adopted with a positive NPV, by how many days should the average collection time be reduced at a minimum? Fractional answers are OK. (Assume 365 days in a year.)

	4.32
	4.43
	4.54
	4.64
	4.75