Final answer:
The relationship between the first 4 and the second 4 in 74,421 lies in their place values, with the first 4 being in the thousands place and the second 4 in the tens place, indicating they represent different magnitudes (4,000 and 40, respectively).
Step-by-step explanation:
The relationship between the first 4 and the second 4 in the number 74,421 is determined by their position within the number. The first 4 is in the thousands place, representing 4,000, while the second 4 is in the tens place, representing 40. Therefore, when adding numbers like 4,200 and 540, we get a result of 4,740, and we round to the nearest whole number since both starting numbers have 0 decimal places.
To determine the significance of each digit in a number, we can employ place value, which tells us that the first 4, being in the thousands place, is ten times greater than the second 4, which is in the tens place. In an exercise of adding, subtracting, or other mathematical operations, the digits would contribute differently based on their place value positions.