Which fraction is the reciprocal of 6 3/4

The doubling period of a bacterial population is 20 20 minutes. At time t = 100 t=100 minutes, the bacterial population was 9000

Nuetrik [128]

Answer:

The initial population was 2810

The bacterial population after 5 hours will be 92335548

Step-by-step explanation:

The bacterial population growth formula is:

$P = P_0 \times e^{rt}$

where P is the population after time t, $P_0$ is the starting population, i.e. when t = 0, r is the rate of growth in % and t is time in hours

Data: The doubling period of a bacterial population is 20 minutes (1/3 hour). Replacing this information in the formula we get:

$2 P_0 = P_0 \times e^{r 1/3}$

$2 = e^{r \; 1/3}$

$ln 2 = r \; 1/3$

$ln 2 \times 3 = r$

$2.08 \% = r$

Data: At time t = 100 minutes (5/3 hours), the bacterial population was 90000. Replacing this information in the formula we get:

$90000 = P_0 \times e^{2.08 \; 5/3}$

$\frac{9000}{e^{2.08 \; 5/3}} = P_0$

$2810 = P_0$

Data: the initial population got above and t = 5 hours. Replacing this information in the formula we get:

$P = 2810 \times e^{2.08 \; 5}$

$P = 92335548$

3 0

3 years ago

What is the result of the division? 2x^3-5x*4 —————- x-3

gtnhenbr [62]

Answer:

2 x 2 + 6 x + 13 + 43 x − 3

2x2+6x+13+43x-3

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

2.-3(x-2) OS (1 Point) Enter your answer

Fantom [35]

Answer:

-3x+6

Step-by-step explanation:

Again, you multiply -3 times x and you get -3x, then you multiply -3 times -6 and since you are multiplying two negative numbers the result becomes positive so you get +6. Result = -3x+6

6 0

3 years ago

Solve each equation. 7) 18 =-2+a 8) -7= m - 12 9) -8(7 + 7n)=-336 10) -140=-7(-4+36)

lesya692 [45]

Answer:

7) a= 20

8) m= 5

9)n = 5

10) b = 8

Step-by-step explanation:

7) 18+2=-2+2+a

>> 20 = a >> a = 20

18 + 2 = 20 so that isolates the variable leaving a = 20

8) -7+12 = m -12+12

>>> 5 = m >> m = 5

-7 + 12 = 5 so that again isolates the variable leaving m = 5

9) -8(7 + 7n) = -336

>> -56+56 + -56n = -336+56

>>> -56n/-56 = -280/-56

>>>> n = 5

use distributive property, cancel out necessary numbers, isolate the variable. leaving n = 5.

10) -140 = -7(-4 + 3b)

>> -140 = 28 - 21b >> -140-28 = -21b +28-28 ( flipped the numbers)

>>> -168/-21 = -21b /-21

>>>> 8 = b >> b =8

Hope it helps!

5 0

3 years ago

Find the critical value of x2 based on the given information H1 >3.5 n=14 a=0.05

egoroff_w [7]

Answer:

The degrees of freedom are given by:

$df = n-1=14-1=13$

The significance level is $\alpha=0.05$ and then the critical value can be founded in th chi square table we need a quantile that accumulates 0.05 of the area in the right tail of the distribution and for this case is:

$\chi^2_{\alpha}= 22.362$

And if the chi square statistic is higher than the critical value we can reject the null hypothesis in favor of the alternative.

Step-by-step explanation:

We have the followign system of hypothesis:

Null hypothesis: $\sigma^2 \leq 3.5$

Alternative hypothesis: $\sigma^2 >3.5$

The degrees of freedom are given by:

$df = n-1=14-1=13$

The significance level is $\alpha=0.05$ and then the critical value can be founded in th chi square table we need a quantile that accumulates 0.05 of the area in the right tail of the distribution and for this case is:

$\chi^2_{\alpha}= 22.362$

And if the chi square statistic is higher than the critical value we can reject the null hypothesis in favor of the alternative.

4 0

3 years ago