8. Use mental math to multiply. a) 235 times 0.1, b) 235 times 0.01, c) 876 times 0.01, d) 876 times 0.001,

Please help me please i really need help please help me

Delicious77 [7]

Answer:

The formula of the volume of a cylinder is known as follow

Where

π is 3,14 or 22/7.

d (diameter) is a straight line segment that crosses a center and connects two points on the circle.

r is the radius of the to part of the cylinder.

h is the height.

we can subsitute to our formula knowing that

d = 4cm (turn to r = <em>2cm</em>,because the formula use r) ; h = 11cm

V = πr²h

= 3,14 × 2² × 11

= 3,14 × 4 × 11

= 3,14 × 44

= 138,16 rounded off (138,2cm3) result

5 0

3 years ago

Select the correct answer. Which number has a repeating decimal form? A. 15 B. 11/25 C. 3/20 D. 2/6

ivanzaharov [21]

Answer:

Step-by-step explanation: im pretty sure that its b so there you go

4 0

3 years ago

Read 2 more answers

Write the equation of a line in slope-intercept form that passes through the given points.

ruslelena [56]

Answer:

Step-by-step explanation:

$\bold{slope\, (m)=\dfrac{change\ in\ Y}{change\ in\ X}=\dfrac{y_2-y_1}{x_2-x_1}}$

(0, 2) ⇒ x₁ = 0, y₁ = 2

(-4, 1) ⇒ x₂ = -4, y₂ = 1

So the slope:

$\bold{m=\dfrac{1-2}{-4-0}=\dfrac{-1}{-4}=0.25}$

The point-slope form of the equation of the line passing through point (x₀,y₀) and with slope m is: y - y₀ = m(x - x₀)

m = 0.25

(0, 2) ⇒ x₀ = 0, y₀ = 2

Therefore:

y - 2 = 0.25(x - 0)

y - 2 = 0.25x {add 2 to both sides}

y = 0.5x + 2 ← the slope-intercept form of the equation

5 0

3 years ago

The number of undergraduates at Johns Hopkins University is approximately 2000, while the number at Ohio State University is app

Likurg_2 [28]

The remaining part of Question:

4) what can we conclude about sampling variability in the sample proportion calculated in the sample at John Hopkins as compared to that calculated in the sample at Ohio State.

5) The number of undergraduates at Johns Hopkins is approximately 2000 while the number at Ohio State is approximately 40000, suppose instead that at both schools, a simple random sample of about 3% of the undergraduates Will be taken.

Answer:

4) The sample proportion from Johns Hopkins will have about the same sampling variability as that from Ohio State

5) The sample proportion from John Hopkins will have more sampling variability than that from Ohio State

Step-by-step explanation:

Note: The sampling variability in the sample proportion decreases with increase in the sample size.

4) since the sample size at both Johns Hopkins and Ohio State is the same (i.e. n = 50), the sample variability of the sample proportion will be the same for both cases.

5) 3% of the population are selected for the observation in both cases.

At Johns Hopkins, sample size, n = 3% * 2000

n = 60

At Ohio State, sample size, n = 3% * 40000

n = 1200

Since sampling variability in the sample proportion decreases with increase in the sample size, the sampling variability in sample proportion will be higher at Johns Hopkins than at Ohio State.

5 0

3 years ago

4. Using the geometric sum formulas, evaluate each of the following sums and express your answer in Cartesian form.

nikitadnepr [17]

Answer:

$\sum_{n=0}^9cos(\frac{\pi n}{2})=1$

$\sum_{k=0}^{N-1}e^{\frac{i2\pi kk}{2}}=0$

$\sum_{n=0}^\infty (\frac{1}{2})^n cos(\frac{\pi n}{2})=\frac{1}{2}$

Step-by-step explanation:

$\sum_{n=0}^9cos(\frac{\pi n}{2})=\frac{1}{2}(\sum_{n=0}^9 (e^{\frac{i\pi n}{2}}+ e^{\frac{i\pi n}{2}}))$

$=\frac{1}{2}(\frac{1-e^{\frac{10i\pi}{2}}}{1-e^{\frac{i\pi}{2}}}+\frac{1-e^{-\frac{10i\pi}{2}}}{1-e^{-\frac{i\pi}{2}}})$

$=\frac{1}{2}(\frac{1+1}{1-i}+\frac{1+1}{1+i})=1$

2nd

$\sum_{k=0}^{N-1}e^{\frac{i2\pi kk}{2}}=\frac{1-e^{\frac{i2\pi N}{N}}}{1-e^{\frac{i2\pi}{N}}}$

$=\frac{1-1}{1-e^{\frac{i2\pi}{N}}}=0$

3th

$\sum_{n=0}^\infty (\frac{1}{2})^n cos(\frac{\pi n}{2})==\frac{1}{2}(\sum_{n=0}^\infty ((\frac{e^{\frac{i\pi n}{2}}}{2})^n+ (\frac{e^{-\frac{i\pi n}{2}}}{2})^n))$

$=\frac{1}{2}(\frac{1-0}{1-i}+\frac{1-0}{1+i})=\frac{1}{2}$

What we use?

We use that

$e^{i\pi n}=cos(\pi n)+i sin(\pi n)$

and

$\sum_{n=0}^k r^k=\frac{1-r^{k+1}}{1-r}$

6 0

3 years ago