Kaplan kit question KXP CO.

I have a problem calculating the average receivables, i am using the method you explained in the OT lecture notes example. The question states: In order to encourage customers to pay on time, KXP Co. proposes introducing an early settlement discount of 1% for payment within 30 days, while increasing its normal credit period to 45 days. It is expected that, on average, 50% of customers will take the discount and pay within 30 days, 30% will pay after 45 days and 20% will not change their current paying behavior. Current receivables are $2,466,000 given in the question. what i did: 30 days x 0.5 = 15 45 days x 0.3 = 13.5 60 days x 0.2 = 12 avg. collection period 41 days soo avg. receivables= 41/365 x $15m sales = $1,684,932 But according to the answer in the kaplan kit the avg. receivables figure is different kaplan kit answer: (15mx0.5x30/365)+(15m x 0.3 x 45/365)+(15mx0.2x60/365)=$1,644,384 kindy point out what i did wrong thanks