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3 years ago

12

I need help plz will give brainliest!!!

1 answer:

Leokris [45]3 years ago

7 0

Answer:

18 red marbles

Step-by-step explanation:

Because the ratio of yellow marbles to red marbles is 1:6 in the population, the expected number of red marbles is 6 times the number of yellow marbles in the representative sample. there should be 18 red marbles.

You might be interested in

Find f. f ″(x) = x^−2, x > 0, f(1) = 0, f(6) = 0

marin [14]

If you do in fact mean $f(1)=f(6)=0$ (as opposed to one of these being the derivative of $f$ at some point), then integrating twice gives

$f''(x) = -\dfrac1{x^2}$

$f'(x) = \displaystyle -\int \frac{dx}{x^2} = \frac1x + C_1$

$f(x) = \displaystyle \int \left(\frac1x + C_1\right) \, dx = \ln|x| + C_1x + C_2$

From the initial conditions, we find

$f(1) = \ln|1| + C_1 + C_2 = 0 \implies C_1 + C_2 = 0$

$f(6) = \ln|6| + 6C_1 + C_2 = 0 \implies 6C_1 + C_2 = -\ln(6)$

Eliminating $C_2$ , we get

$(C_1 + C_2) - (6C_1 + C_2) = 0 - (-\ln(6))$

$-5C_1 = \ln(6)$

$C_1 = -\dfrac{\ln(6)}5 = -\ln\left(\sqrt[5]{6}\right) \implies C_2 = \ln\left(\sqrt[5]{6}\right)$

Then

$\boxed{f(x) = \ln|x| - \ln\left(\sqrt[5]{6}\right)\,x + \ln\left(\sqrt[5]{6}\right)}$

3 0

2 years ago

What is the solution of the equation (x – 5)^2 + 3(x – 5) + 9 = 0? Use u substitution and the quadratic formula to solve.

xz_007 [3.2K]

Answer:

$x = \dfrac{7 \pm 3i\sqrt{3}}{2}$

Step-by-step explanation:

(x – 5)^2 + 3(x – 5) + 9 = 0

This is a quadratic equation in x - 5.

Let u = x - 5, then the quadratic equation becomes:

u^2 + 3u + 9 = 0

We can use the quadratic formula to solve for u.

$u = \dfrac{-b \pm \sqrt{b^2 - 4ac}}{2a}$

$u = \dfrac{-3 \pm \sqrt{3^2 - 4(1)(9)}}{2(1)}$

$u = \dfrac{-3 \pm \sqrt{9 - 36}}{2}$

$u = \dfrac{-3 \pm \sqrt{-27}}{2}$

$u = \dfrac{-3 \pm 3i\sqrt{3}}{2}$

Since u = x - 5, now we substitute x - 5 for u and solve for x.

$x - 5 = \dfrac{-3 \pm 3i\sqrt{3}}{2}$

$x = \dfrac{-3 \pm 3i\sqrt{3}}{2} + 5$

$x = \dfrac{-3 \pm 3i\sqrt{3}}{2} + \dfrac{10}{2}$

$x = \dfrac{7 \pm 3i\sqrt{3}}{2}$

7 0

3 years ago

Pre college need help

NARA [144]

Answer:

C

Step-by-step explanation:

5 0

3 years ago

One US dollar is currently worth 0.79 euro (€). If you exchange $522 for euros, how many euros will you have?

Lapatulllka [165]

I'm pretty sure you would have 412.38 (€) because the equation would be $522 × 0.79.

6 0

3 years ago

Consider the following least-squares specification between test scores and the student-teacher ratio:

liraira [26]

Answer:

Option B

Step-by-step explanation:

Given that the regression equation using least squares for test scores and student teacher ratio is

Test Score = 557.8 + 36.42 In (Income).

Say if 1% income is increased.

Let income be 100

New income = 101

Then we have

Test score original =

$557.8+36.42 Ln 100\\= 725.520$

Test score new income

= $557.8+36.42 ln (101)\\= 725.882$

Increase = 0.362~0.36

Option B is right.

6 0

3 years ago