19. On a certain day, there were 104 pennies in jar A and 20 pennies in jar B. On each subsequent day, 3 pennies were removed from jar A and 4 pennies were added to jar B until the jars had the same number of pennies. On how many days were pennies removed from jar A?
Answer: C
12 days were required for the jars to have the same number of pennies.
After 12 days of removing 3 pennies from jar A and adding 4 pennies to jar B, both jars will contain the same number of pennies.
A) 8
If only 8 days were considered, then jar A would have lost 24 pennies, resulting in 80 pennies, while jar B would have gained 32 pennies, totaling 52 pennies. This does not result in an equal amount of pennies in both jars.
B) 10
After 10 days, jar A would have 70 pennies (104 - 30) and jar B would have 60 pennies (20 + 40). Though this is a significant increase for jar B, the number of pennies in both jars would still not be equal.
C) 12
At 12 days, jar A would have 40 pennies left (104 - 36) and jar B would have 68 pennies (20 + 48). This means that after the 12th day, both jars equalize at 68 pennies, confirming that 12 days is indeed the correct answer.
D) 14
If 14 days were taken into account, jar A would have 22 pennies remaining (104 - 42), while jar B would have 68 pennies (20 + 56). This results in an inequality between the two jars, thus disproving this option.
E) 16
After 16 days, jar A would be left with only 10 pennies (104 - 48), while jar B would have 88 pennies (20 + 64). Again, this does not result in equal amounts, invalidating this choice as well.
Conclusion
The calculations confirm that 12 days of removing pennies from jar A is the only option that results in both jars containing the same number of pennies. All other options fail to achieve equality between the jars within the specified timeline.