Exponential growth and decay word problems
Model percent growth or decay over time and estimate the amount after t periods. Unlimited questions, five difficulty levels, and a full worked solution every time — free.
Try one
Right now, a stocked fish population in a conservation lake is 800. It grows by 20% every year. Estimate the amount after 3 years, rounded to the nearest whole fish.
Answer: 1382
See one solved, step by step
Right now, the population of a small town near Sudbury is 160. It grows by 20% every year. Estimate the amount after 5 years, rounded to the nearest whole person.
📘 Worked solution
1Growth factor = 1 + 20100 = 1.2Growth adds a percent of the amount each year, so add the rate to 1.
2A(5) = 160 · 1.25Multiply the starting amount by the growth factor raised to the number of years.
3= 160 · 2.4883 = 398.13 -> 398Round to the nearest whole person, since a fractional person doesn't make sense.
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