A substance decays at rate 4 each year If there is 1500mg to

A substance decays at rate 4% each year. If there is 1500mg to start how much will be left after 12 years?

Solution

A city has a population of 50,000 people. Over a span of 8 years the city saw a population growth of 5% each year. What was the new population at the end of year 8?

initial population P=50000

continously grows at rate =5% each year

=>r =0.05

population after t years =Pe^rt

population at the end of year 8  =50000*e^0.05*8

population at the end of year 8  =74591 people

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A substance decays at rate 4% each year. If there is 1500mg to start how much will be left after 12 years?

let initial amount of substace P=1500mg

continously decay at rate =4% per year

=>r =-0.04

amount after t years A =Pe^rt

after 12 years amount left =1500*e^-0.04*12

after 12 years amount left =928.1754

after 12 years amount left =928.2 mg

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