pre calc
A 50 gram sample of radioactive strontium will decay to 32 grams in 18 years.
a. Find an equation that will model how much of our sample M will remain after t years.
asked by
andi

(5032)grams/18yrs = 1 Gram/yr.
Mr = M1*T = MT = 50  18 = 32 grams. = Mass remaining.
posted by Henry

Correction: The decay rate is exponential.
50/e^x = 32, e^x = 50/32 = 1.5625, X = 0.446 = kt, K = 0.446/t = 0.446/18 = 0.0248.
Mr = M/e^kt = M/e^(0.0248t) = Mass remaining.
posted by Henry
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