I would GREATLY appreciate it if you could help me. (WORTH 10+ POINTS.) Joan went on a 3 day road trip to visit her best friend in North Carolina; she drove a total of 320.7 miles on the trip. The first day Joan drove 118.75 miles, on day two she drove 95.4 miles. How many miles must she have driven on the third day?

Part B: If Joan wanted to take a more scenic route home, her new total mileage would be 385.5 How many more miles is her trip home than her trip to North Carolina?

for this case we must apply distributive property to the following expression:

the distributive property states that:

then, when applying the property we have to multiply the -2 for each term within the parenthesis:

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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