Suppose a city with population 300,000 has been growing at a rate of ​7% per year. If this rate​ continues, find the population of this city in 22 years.

Answer 1

A = P(b)^t

A = New Amount

P = Starting Amount

b = Growth rate (b > 1 (100%) for growth; b < 1 for decay » b = 100% + 7% = 1.07

t = Period of growth rate

A = 300,000(1.07)²²

A = 1,329,120

Answer 2

Hi Paige,

Assuming linear growth, we can use the y=mx+b setup to come up with the equation! the "b" value is our starting point- in this case it's 300,000. "m," our slope, will be 7% of that; (.07)(300000) = 21,000

Combining these results, we get the equation:

y = 21000x+300000

Plugging in x=22, we get a population of 762,000.