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NISA [10]
2 years ago
15

A scientist running an experiment starts with 100 bacteria cells. These bacteria double their population every 15 hours. Find ho

w long it takes for the bacteria cells to increase to 300. Use the formula , where is the original number of bacteria cells, is the number after t hours, and d is the time taken to double the number. It takes hours for the number of bacteria to increase to 300.
Mathematics
2 answers:
IRISSAK [1]2 years ago
8 0
<h2>Hello!</h2>

The answer is: 23.77 hours

<h2>Why?</h2>

Total(t)=Start*2^\frac{t}{15}

Where:

Total(t) is equal to the amount for a determined time (in hours)

<em>Start</em> is the original amount

<em>t </em>is the time in hours.

For example, it's known from the statement that the bacteria double their population every 15 hours, so it can be written like this:

Total(15)=100*2^\frac{15}{15}=100*2^{1}=100*2=200

To calculate how long it takes for the bacteria cells to increase to 300, we should do the following calculation:

300=100*2^{\frac{t}{15} } } \\\frac{300}{100}=2^{\frac{t}{15} } }\\log(3)=log(2^{\frac{t}{15} })\\\\\\log(3)=\frac{t}{15}*log2\\t=\frac{log(3)}{log(2)} *15=23.77

So, to know if we are right, let's replace 23.77 h in the equation:

Total(t)=100*2^\frac{23.77}{15}=299.94

and 299.94≅300

Have a nice day!

Rina8888 [55]2 years ago
3 0

Answer:

23.77

Step-by-step explanation:

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There are total 5 layers.

Step-by-step explanation:

A multi-layer cake is in the shape of a right cylinder.

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h=\frac{1250}{314}

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2 years ago
The Chang family is on their way home from a cross-country road trip. During the trip, the function D(t) = 2,280 - 60t can be us
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7 0
2 years ago
A store sells yogurt in small, medium, and large sizes. A small yogurt costs $2, a medium costs $3, and a large costs $5. In one
lidiya [134]
Let S = number of small yogurts ($2 each).
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Total revenue generated is $98, therefore
2S + 3M +5L = 98

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These three equations may be written as the matrix equation
[  1   1   1  | |S|      |27|
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8 0
2 years ago
A theatre has the capacity to seat people across two levels, the Circle and
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Answer: 76.19\%

Step-by-step explanation:

<h3> The complete exercise is: " A theatre has the capacity to seat people across two levels, the Circle, and the stalls. The ratio of the number of seats in the circle to a number of seats in the stalls is 2:5. Last Friday, the audience occupied all the 528 seats in the circle and \frac{2}{3} of the seats in the stalls. What is the percentage of occupancy of the theatre last Friday?"</h3>

Let be "s" the total number of seats in the Stalls.

The problem says that the ratio of the number of seats in the Circle to the number of seats in the Stalls is 2:5.

Since the number of seats that were occupied last Friday was 528 seats, we can set up the following proportion:

\frac{2}{5}=\frac{528}{s}

Solving for "s", we get:

s*\frac{2}{5}=528\\\\s=528*\frac{5}{2}\\\\s=1,320

So the sum of the number of seats in the Circle and the number of seats in the Stalls, is:

Total=1,320\ seats+528\ seats=1,848\ seats

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(1,320)(\frac{2}{3})=880

Therefore, the total number of seats that were occupied las Friday is:

Total\ occupied=880\ seats+528\ seats=1,408\ seats

Knowing this, we can set up the following proportion, where "p" is the the percentage of occupancy of the theatre last Friday:

\frac{100}{1,848}=\frac{p}{1,408}

Solving for "p", we get:

(1,408)(\frac{100}{1,848})=p\\\\p=76.19\%

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1 year ago
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Answer:

Step-by-step explanation:

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Then we get 4/15y = -17/21. Dividing by 4/15 gets us -17/21 * 4/15 = -68/315 = y.

4 0
2 years ago
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