Collection of a $3000 accounts receivable decreases a liability $3000; increases owner's equity $3000. decreases an asset $3000; decreases a liability $3000. increases an asset $3000; decreases an asset $3000. increases an asset $3000; decreases a liability $3000.

increases an asset $3000; decreases an asset $3000.

Explanation:

The Account Recievable represent the amount of cash the firm can claim to their customers. It is a right thus, an asset.

When we collect from the customer, this right is no more, it disappear thus, the asset (account receivable) decrease.

Along with this decrease in assets, we got an increase in assets for the amount of cash collected, therefore an asset increase too.

The net effect is null. An asset(AR) decreses for 30,000 and another assets(Cash) increases for 30,000.