MATHEMATICS MIDDLE SCHOOL

At t=2 hours, the populations of bacteria colony was 456 and at 4.2 hours, the population was 988. At what time can we expect the population to be 8700?

Answers

Answer 1
Answer:

Answer:

  10.4 hours

Step-by-step explanation:

It is convenient to write the exponential growth function in these terms:

  population = (initial value)·((value at later time)/(initial value))^exponent

where ...

  exponent = (t - (initial time))/(time difference to later time)

Here, we have ...

  • initial value = 456
  • initial time = 2 . . . hours
  • value at later time = 988
  • time difference to later time = 4.2 -2 = 2.2 . . . hours

So, the exponential function is ...

  p(t) = 456·(988/456)^((t-2)/2.2)

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We can find t for p(t) = 8700 a couple of ways. My favorite is to use a graphing calculator to find t such that ...

  p(t) -8700 = 0

This shows t ≈ 10.4 hours.

__

Alternatively, you can solve the equation using algebra.

  8700 = 456·(988/456)^((t-2)/2.2)

  8700/456 = (988/456)^((t-2)/2.2) . . . . . . . . . . .divide by 456

  log(8700/456) = (t -2)/2.2 · log(988/456) . . . . taking logs

  2.2·log(8700/456)/log(988/456) = t -2 . . . . . . multiply by the inverse of the coefficient of t

  t = 2 + 2.2(log(8700/456)/log(988/456)) ≈ 10.389774

We can expect the population to be 8700 at 10.4 hours.

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A regular hexagonal pyramid whose base perimeter is 60cm has an altitude of 30cm. The volume of the pyramid is??

Answers

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I am facing east, then I turn through one hundred and eighty degrees.What direction am I facing now

Answers

You are now on West. 180 degrees is straight. If you walk straight from any angle of a circle on any start of East, West is what you step on.  
the Answer to this question is:West.
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Chantelle takes out a loan of $3,500 with an APR of 4.25%. She will repay the loan in monthly payments for 6 months. To find the total amount of interest she will pay, Chantelle uses an online calculator. What are the correct numbers she should enter?

Answers

Answer:

Chantelle will pay $73 of interest for a loan of $3,500 with an APR of 4.25%.

Step-by-step explanation:

Since APR is  defined as the anual percentage rate, the amount of interest that Chantelle will pay  can be expressed as:

I=L*(1+APR/100%)^n-L

Where L is the amount of money borrewed  and n the numbers of years. As Chantelle repay the loan in less than a year n is less than 1:

n = 6 months / 12 months = 0.5

Then replacing the calculated value of n, the ARP and the the borrowed money:

I=$3,500*(1+4.25%/100%)^0.5-$3,500

I=$3,500*(1+0.0425)^0.5-$3,500

I=$3,500*1.021-$3,500

I=$3,573-$3,500

I=$73

APR = Annual Percentage Rate

[(3500x0.0425)+3500]/2

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Answers

Answer:

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Step-by-step explanation:

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Step-by-step explanation:

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Answers

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Answers

                 Green Salad Macaroni & Cheese French Fries Cole Slaw
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Number of orders of 2 pcs of chicken with green salad.
33 orders.

Experimental probability:
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