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3 years ago

The science center has 200 people in attendance on Monday. The center expects Saturday's attendance to be 140

Mathematics

2 answers:

sammy [17]3 years ago

8 0

Answer:

Step-by-step explanation:

Molodets [167]3 years ago

5 0

Answer:

Natasha should have multiplied 140 by 2

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I dont get this simple math 3 2/1÷ 4/3=

mel-nik [20]

uhm I can't help with that... sorry

7 0

3 years ago

Find the mass of the lamina that occupies the region D = {(x, y) : 0 ≤ x ≤ 1, 0 ≤ y ≤ 1} with the density function ρ(x, y) = xye

Alona [7]

Answer:

The mass of the lamina is 1

Step-by-step explanation:

Let $\rho(x,y)$ be a continuous density function of a lamina in the plane region D,then the mass of the lamina is given by:

$m=\int\limits \int\limits_D \rho(x,y) \, dA$ .

From the question, the given density function is $\rho (x,y)=xye^{x+y}$ .

Again, the lamina occupies a rectangular region: D={(x, y) : 0 ≤ x ≤ 1, 0 ≤ y ≤ 1}.

The mass of the lamina can be found by evaluating the double integral:

$I=\int\limits^1_0\int\limits^1_0xye^{x+y}dydx$ .

Since D is a rectangular region, we can apply Fubini's Theorem to get:

$I=\int\limits^1_0(\int\limits^1_0xye^{x+y}dy)dx$ .

Let the inner integral be: $I_0=\int\limits^1_0xye^{x+y}dy$ , then

$I=\int\limits^1_0(I_0)dx$ .

The inner integral is evaluated using integration by parts.

Let $u=xy$ , the partial derivative of u wrt y is

$\implies du=xdy$

and

$dv=\int\limits e^{x+y} dy$ , integrating wrt y, we obtain

$v=\int\limits e^{x+y}$

Recall the integration by parts formula: $\int\limits udv=uv- \int\limits vdu$

This implies that:

$\int\limits xye^{x+y}dy=xye^{x+y}-\int\limits e^{x+y}\cdot xdy$

$\int\limits xye^{x+y}dy=xye^{x+y}-xe^{x+y}$

$I_0=\int\limits^1_0 xye^{x+y}dy$

We substitute the limits of integration and evaluate to get:

$I_0=xe^x$

This implies that:

$I=\int\limits^1_0(xe^x)dx$ .

$I=\int\limits^1_0xe^xdx$ .

We again apply integration by parts formula to get:

$\int\limits xe^xdx=e^x(x-1)$ .

$I=\int\limits^1_0xe^xdx=e^1(1-1)-e^0(0-1)$ .

$I=\int\limits^1_0xe^xdx=0-1(0-1)$ .

$I=\int\limits^1_0xe^xdx=0-1(-1)=1$ .

No unit is given, therefore the mass of the lamina is 1.

3 0

3 years ago

Sophia wanted to knit a scarf 1 meters long. On Monday, she knit

Sergio [31]

She knit 1/4 of the total length of the scarf on monday

Answer:

She knit 7/10 of the scarf altogether

Step-by-step explanation:

Please see the attached file for explanation

3 0

3 years ago

Simplify

aleksandr82 [10.1K]

Answer:

A. 7- i

B. -20 -10i

C. 50

D. -1 +2i

Step-by-step explanation:

7 0

3 years ago

Find the measure of angle A. 66° x +49 x+83

liubo4ka [24]

Step-by-step explanation:

Since , internal sum of angle of triangle is 180°

So,

66 + x +49 + x+83 = 180

or, 198 + 2x = 180

or, 2x = 180 -198

or, 2x = -18

hence, x = - 9

Now angle A = x + 49

= (-9) + 49

= 40

Hence measure of angle A is 40°.

8 0

2 years ago

Read 2 more answers