The bird population in louisiana is decreasing at a rate of 15% per day due to the oil spill. if there are 12,000 birds today, how many will there be three weeks from now?

Work Shown:

The formula to use is

A = P*(1+r)^x

where,

P = 12000 is the initial population

r = -0.15 represents the growth rate in decimal form; which is really a decay/decrease due to r being negative

x = 21 days have passed by (3 weeks = 3*7 = 21 days)

These values lead to...

A = P*(1+r)^x

A = 12000*(1+(-0.15))^21

A = 12000*(1-0.15)^21

A = 12000*(0.85)^21

A = 12000*0.03294560142183

A = 395.34721706196

A = 395

b. astronomers