If ONLY the digit 4 in the number 847 is changed to a different digit, by how much could the number change?

Answer

To solve this problem, we need to analyze how changing the digit '4' in the number '847' affects its overall value. The digit '4' represents the tens place in the number 847, which is composed as follows: - 8 in the hundreds place (8 x 100 = 800) - 4 in the tens place (4 x 10 = 40) - 7 in the units place (7 x 1 = 7) This gives us: 847 = 800 + 40 + 7. Now, we recognize that if we change '4' to any other digit (0-9), we will be altering the tens value. Let's work through the maximum possible change: - If we change '4' to '0', the new number would be: 8(0)7 = 807. The change would be: 847 - 807 = 40. - If we change '4' to '9', the new number would be: 8(9)7 = 897. The change would be: 897 - 847 = 50. The other digits between those can give changes like: 1 (837), 2 (827), 3 (817), 4 (847 - stays the same, no change) and 5, (857), amounting to changes based on their respective values. The maximum change occurs when changing '4' to '0' or '9'. - Changing to '0' gives us a reduction of 40 (847 to 807). - Changing to '9' gives us an increase of 50 (847 to 897). Thus the total numeric changes we observe can total 50 units as the highest option readily fitting our quiz selection options. Therefore, the only feasible answer illustrating a valid change over this numeric transformation could only yield a difference of 50. Thus the answer would be: C. 50.