Forms :: Distribute Master Block Total Amount In Detail Block Line Wise

i have a master detail form, In Master block we have one field cheque amount and in Detail block we have field receiveable amount invoice wise. if company paid us a cheque amount we will enter this amount in Master block field Cheque amount and in detail block there will be invoice wise receivable amounts. i want to distribute the cheque amount in detail block invoice wise for example

Cheque amount in master block = 291

Invoice wise receiveable amount is as follows

Invoice No , receivable amount , Received amount

10, 196 , 0
20 , 95 , 0
30 , 54 , 0

Result should be as follows:

Invoice No , receivable amount , Received amount

10, 196, 196
20 , 95 , 95
30 , 54, 0

Received amount field should be distributed according to the receivable amount when recevied amount = cheque amount then remaining will be 0.