First, let's calculate the total amount of milk the shopkeeper bought over the two days.

**Monday Morning:**
- 60 packets of 250 ml = 60 * 250 ml
- 40 packets of 300 ml = 40 * 300 ml
- Remaining packets (150 - 60 - 40) of 350 ml = 50 * 350 ml

**Monday Evening:**
- 50% of 100 packets of 400 ml = 0.5 * 100 * 400 ml
- 25% of 100 packets of 500 ml = 0.25 * 100 * 500 ml
- Remaining packets (100 - 50% - 25%) of 450 ml = 0.25 * 100 * 450 ml

**Tuesday Morning:**
- 40% of 60 packets of 300 ml = 0.4 * 60 * 300 ml
- 30% of 60 packets of 350 ml = 0.3 * 60 * 350 ml
- Remaining packets (60 - 40% - 30%) of 400 ml = 0.3 * 60 * 400 ml

**Tuesday Evening:**
- 25% of 200 packets of 450 ml = 0.25 * 200 * 450 ml
- 35% of 200 packets of 500 ml = 0.35 * 200 * 500 ml
- Remaining packets (200 - 25% - 35%) of 550 ml = 0.4 * 200 * 550 ml

Now, let's calculate the total amount of milk bought each day:

**Monday:**
- Morning: (60 * 250) + (40 * 300) + (50 * 350) = 15,000 + 12,000 + 17,500 = 44,500 ml
- Evening: (0.5 * 100 * 400) + (0.25 * 100 * 500) + (0.25 * 100 * 450) = 20,000 + 12,500 + 11,250 = 43,750 ml
- Total for Monday: 44,500 + 43,750 = 88,250 ml

**Tuesday:**
- Morning: (0.4 * 60 * 300) + (0.3 * 60 * 350) + (0.3 * 60 * 400) = 7,200 + 6,300 + 7,200 = 20,700 ml
- Evening: (0.25 * 200 * 450) + (0.35 * 200 * 500) + (0.4 * 200 * 550) = 22,500 + 35,000 + 44,000 = 101,500 ml
- Total for Tuesday: 20,700 + 101,500 = 122,200 ml

**Total milk bought over two days:**
88,250 ml (Monday) + 122,200 ml (Tuesday) = 210,450 ml

The shopkeeper has 84,000 ml of milk left in his inventory. To find out how much he sold, we subtract the remaining milk from the total milk bought:

210,450 ml (total bought) - 84,000 ml (left) = 126,450 ml (sold)

Now, we convert the sold milk from milliliters to fluid ounces using the conversion rate 1 fluid ounce = 30 ml:

126,450 ml / 30 ml/fl oz = 4,215 fl oz

Therefore, the shopkeeper sold 4,215 fluid ounces of milk to his customers over those two days.
먼저 이틀 동안 가게 주인이 구매한 우유의 총량을 계산해 보겠습니다.

**월요일 아침:**
- 250ml 60팩 = 60 * 250ml
- 300ml 40팩 = 40 * 300ml
- 350ml 남은 패킷(150 - 60 - 40) = 50 * 350ml

**월요일 저녁:**
- 400ml 100팩의 50% = 0.5 * 100 * 400ml
- 500ml 100팩의 25% = 0.25 * 100 * 500ml
- 450ml의 나머지 패킷(100 - 50% - 25%) = 0.25 * 100 * 450ml

**화요일 아침:**
- 300ml 60팩의 40% = 0.4 * 60 * 300ml
- 350ml 60팩의 30% = 0.3 * 60 * 350ml
- 400ml의 나머지 패킷(60 - 40% - 30%) = 0.3 * 60 * 400ml

**화요일 저녁:**
- 450ml 200팩의 25% = 0.25 * 200 * 450ml
- 500ml 200팩의 35% = 0.35 * 200 * 500ml
- 550ml의 나머지 패킷(200 - 25% - 35%) = 0.4 * 200 * 550ml

이제 매일 구매한 우유 총량을 계산해 보겠습니다:

**월요일:**
- 아침: (60 * 250) + (40 * 300) + (50 * 350) = 15,000 + 12,000 + 17,500 = 44,500ml
- 저녁: (0.5 * 100 * 400) + (0.25 * 100 * 500) + (0.25 * 100 * 450) = 20,000 + 12,500 + 11,250 = 43,750ml
- 월요일 총액: 44,500 + 43,750 = 88,250ml

**화요일:**
- 아침: (0.4 * 60 * 300) + (0.3 * 60 * 350) + (0.3 * 60 * 400) = 7,200 + 6,300 + 7,200 = 20,700ml
- 저녁: (0.25 * 200 * 450) + (0.35 * 200 * 500) + (0.4 * 200 * 550) = 22,500 + 35,000 + 44,000 = 101,500ml
- 화요일 총액: 20,700 + 101,500 = 122,200ml

**이틀 동안 구매한 총 우유:**
88,250ml(월요일) + 122,200ml(화요일) = 210,450ml

상점 주인은 인벤토리에 84,000ml의 우유가 남아 있습니다. 판매량을 알아내려면 총 구매량에서 남은 우유를 뺍니다:

210,450ml(총 구매량) - 84,000ml(남은 우유) = 126,450ml(판매량)

이제 판매된 우유를 1액량당 30ml의 환산율을 사용하여 밀리리터에서 액량 온스로 변환합니다:

126,450ml / 30ml/fl oz = 4,215 fl oz

따라서 가게 주인은 이틀 동안 고객에게 4,215ml의 우유를 판매했습니다.