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Description:
PSAT 1.17 Math Diagnostic. Which of the following functions models the number of E. coli bacteria at time h?
More Video DetailsTranscript
- 00:00
Thank you We sneak And here's your shmoop du jour
- 00:05
brought to you by e coli Once you've gone e
- 00:08
coli you never go back here yet All right so
- 00:14
check out this info time sudden memory for people down
- 00:20
All right we get it Which of the following functions
Full Transcript
- 00:23
models the number of e coli bacteria at time age
- 00:27
where h represents the number of hours since the experiment's
- 00:30
started And here essential answers All right the functions of
- 00:35
ours All right well first of all it's fine If
- 00:37
you want to leave e coli bacteria on the lab
- 00:39
table But police be sure the labeling last thing you
- 00:42
ever want to have happen is for some unsuspecting fellow
- 00:45
scientist to see the dish and mistaken for his chobani
- 00:48
blended plum yogurt All right well he might be spending
- 00:51
the next three or four hours in the emergency shower
- 00:53
Okay so were given a pretty simple looking table and
- 00:57
we're supposed to use the shadow there to assemble a
- 00:59
written function that represents the number of e coli bacteria
- 01:02
in relation to age the number of hours Well let
- 01:06
zero hours there in just fifteen bacteria in a petri
- 01:09
dish with scientists started out with every hour after that
- 01:13
it looks like they doubled So should be just about
- 01:16
four five days until they take over The world ok
- 01:20
well maybe we're being alarmist here but until they start
- 01:22
growing limbs and learn how to open and close the
- 01:24
door when we should be fine the good news is
- 01:27
that because the reign of growth is constant from one
- 01:30
hour to the next way no that the relationship is
- 01:33
exponential which means we can use this formula Why equals
- 01:38
eight times the quantity One plus our to the x
- 01:41
power well has always pays the initial amount in this
- 01:44
case teen bacteria our is the growth rate one hour
- 01:49
and x is the number of compounding period since we're
- 01:53
using ours is our com pounding period let's replace the
- 01:56
acts within age unless your friends are something in spell
- 02:00
ours with an x in which case well you just
- 02:03
keep it as is we'll also want to replace the
- 02:05
why of the f of age to make it more
- 02:08
you know function and we're left with f of h
- 02:11
g wells fifteen times two to the h power which
- 02:14
is option c if you want to double check to
- 02:17
make sure we set this thing up right We can't
- 02:19
look in any number from the time And we should
- 02:21
get the corresponding data in the table For example we
- 02:24
could plug in three thousand four hundred twenty seven hours
- 02:26
but we really don't want to be here all day
- 02:28
so instead we'll plug in five to two The fifth
- 02:31
power is who four eight sixteen thirty two times fifteen
- 02:36
which is four hundred eighty century enough consulting our table
- 02:40
After five hours there should be four hundred eighty bacteria
- 02:42
in the petri dish Option c It is all right
- 02:45
We've had enough of incredible multiplying bacteria If we wanted
- 02:50
to see something multiplied this fast we watched that new 00:02:53.24 --> [endTime] show on tlc thirty seven isn't enough
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