credit card - billing cycle

[canuckclint]

Please solve:
Makes no sense to me.

[sudhir3127]

Please solve:
Makes no sense to me.

Statement 1:

Payment was made on 21st day. That means for first 20 days balance was $600 each day and from 21st day to 30th day balance was $600 - $300 = $300.

Avrage daily balance for 30 days period = ($600 x 20 (days) + $300x10 (days))/30............................... sufficient


statement 2.

Avrage balance for 25 days cycle was $540. That means $300 was paid some where in between from day 1 to day 25th. We can assume that it was paid after X number of days.

($600* X (days) + $300* (25-X) days)/25 = $540

solve for X ..

hence sufficent ,..

hence D .

Hope that helps