Gain Loss on receipt is split line between gain and loss, How to merge

Example

Transaction No.1  AR 100 USD @ 30 THB/USD

Transaction No. 2 AR 150 USD @ 33 THB/USD

When Receipt those 2 transactions

1. Create Receipt 250 USD @ 31 THB/USD

2. Apply to transaction No.1 then get gain 100 THB

3. Apply to transaction No. 2 then get loss (300) THB

When create accounting for the receipt got this result

Dr. Bank                      250 USD                     7,750 THB

Dr. Loss                                                           300 THB

    Cr. Trans No.1                100 USD                       3,000 THB    

    Cr. Trans No.2                150 USD                       4,950 THB

    Cr, Gain                                                                100 THB

Is there any way to make journal create like below

Dr. Bank                       250 USD                     7,750 THB

Dr. Loss                                                            200 THB

    Cr. Trans No.1                 100 USD                      3,000 THB

    Cr. Trans No.2                 150 USD                      4,950 THB

Is netting of gain/loss is common way to record journal?