Element X is a radioactive isotope such that every 11 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 5600 grams, how much of the element would remain after 10 years, to the nearest whole number?Answer:
Q. Element X is a radioactive isotope such that every 11 years, its mass decreases by half. Given that the initial mass of a sample of Element X is 5600 grams, how much of the element would remain after 10 years, to the nearest whole number?Answer:
Understand the problem: Understand the problem.We need to calculate the remaining mass of a radioactive isotope after 10 years, knowing that it halves every 11 years. The initial mass is 5600 grams.
Determine decay factor per year: Determine the decay factor per year.Since the mass halves every 11 years, we can use the formula for exponential decay to find the decay factor per year. The decay factor is the nth root of 21, where n is the number of years for the mass to halve. In this case, n=11.Decay factor per year = (21)111
Calculate remaining mass after 10 years: Calculate the remaining mass after 10 years.We apply the decay factor for 10 years to the initial mass.Remaining mass = Initial mass × (Decay factor per year)10Remaining mass = 5600×((21)111)10
Perform the calculation: Perform the calculation.First, calculate the decay factor per year:(1/2)1/11≈0.933033Now, apply this factor for 10 years:Remaining mass ≈5600×(0.933033)10Remaining mass ≈5600×0.510/11Remaining mass ≈5600×0.93303310Remaining mass ≈5600×0.510/11Remaining mass ≈5600×0.93303310Remaining mass ≈5600×0.510/11Remaining mass ≈5600×0.93303310
More problems from Exponential growth and decay: word problems