A bacteria population starts at 2,000 and decreases at about 15% per day. use A=P(1-r)^t to write a function representing the number of bacteria present each day. After how many days will there be fewer than 100 bacteria? Round to the nearest tenth of a day.

Question

rebeccaxhawaii · Answer

okay so p=2,000

rebeccaxhawaii · Answer

r is your rate and t is time

squidnnneyyy · Answer

I love these types of problems, ok so first, you plug everything in

squidnnneyyy · Answer

A=200(1-15)^2

First you convert 15 into a decimal

squidnnneyyy · Answer

A=2000(1-0.15)^2

lexy148 · Answer

it would be .15

squidnnneyyy · Answer

Then you subtract 1-0.15 (As stated)

lexy148 · Answer

oh okay i understnd how you got it now

squidnnneyyy · Answer

so then, obviously you just multiply by 2000

lexy148 · Answer

why is there a 2 as the exponent

squidnnneyyy · Answer

oh ya, oops after you subtract  1-0.15, you square that AND THEN multiply

squidnnneyyy · Answer

Do you have the answer?

lexy148 · Answer

why would it be  200 wouldnt it be 2000 for the 1st equation?

lexy148 · Answer

the answer would be 1445

lexy148 · Answer

@Squidnnneyyy