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one 12 oz can of Dr.Pepper contains about 39.4 mg of caffeine. The function A(x)=39.4(0.8342)^x Determine how long after drinking one can of Dr.Pepper will only 4mg of caffeine remain in the body?

User Nicoco
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1 Answer

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Final answer:

The solution is approximately 0.5602 hours or about 33.61 minutes.

Step-by-step explanation:

To determine how long after drinking one can of Dr.Pepper will only 4mg of caffeine remain in the body, we can use the given function A(x) = 39.4(0.8342)^x.

Let's set up the equation A(x) = 4 and solve for x:

4 = 39.4(0.8342)^x

Divide both sides by 39.4:

0.1015 = (0.8342)^x

Take the logarithm of both sides:

log(0.1015) = x log(0.8342)

Divide both sides by log(0.8342) to solve for x:

x = log(0.1015) / log(0.8342)

Using a calculator, we find that x is approximately 0.5602.

Therefore, it will take approximately 0.5602 hours or about 33.61 minutes for only 4mg of caffeine to remain in the body after drinking one can of Dr.Pepper.

User Chrisdinn
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