# Calculus

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The half-life of Palladium-100 is 4 days. After 12 days a sample of Palladium-100 has been reduced to a mass of 4 mg. What was the initial mass (in mg) of the sample? What is the mass 5 weeks after the start?

• Calculus -

amountremaining=Initialamount*e^(.692t/4)
put in given: amount remaining, 12 days, solve for initial amount.

• Calculus -

wgtwgt

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