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4 years ago

Maggie's brother is 9 years younger than three times her age. The sum of their ages is 43. How old is Maggie?

Mathematics

1 answer:

bekas [8.4K]4 years ago

5 0

Answer:

Maggie's age is 13 years

Step-by-step explanation:

Let

x ------> Maggie's brother age

y ------> Maggie's age

we know that

x+y=43 ------ > equation A

x=3y-9 ------> equation B

substitute equation B in equation A and solve for y

(3y-9)+y=43

4y=43+9

4y=52

y=13

therefore

Maggie's age is 13 years

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Please help me answer this will give brainlst

VladimirAG [237]

Answer:

17° and 73°

Step-by-step explanation:

For two complementary angles, the sum of angles is equal to 90 degrees.

Let other angles = x

First angle = 5+4x ...(1)

ATQ,

5+4x+x=90 ...(2)

Equation (1) and (2) shows the equations for the given problems.

5+5x=90

5x = 85

x = 17°

Other angle = 17

First angle = 5+4x

= 5+4(17)

= 73°

So, the other two angles are 17° and 73° respectively.

8 0

3 years ago

20000 students took a standardized math test. The scores on the test are normally distributed, with a mean score of 85 and a sta

Tpy6a [65]

Answer: 2718

Step-by-step explanation:

Given: Mean score = 85

Standard deviation = 5

Let x be the score of a random student that follows normal distribution.

Then, the probability that a student scored between 90 and 95 will be

$P(90< x < 95)\\\\=P(\dfrac{90-85}{5}$

The number of students scored between 90 and 95 = 0.1359 x (Total students)

= 0.1359 (20000)

= 2718

Hence, The number of students scored between 90 and 95 = 2718

7 0

3 years ago

Find Mx, My, and (x, y) for the lamina of uniform density rho bounded by the graphs of the equations. y = x2/3, y = 0, x = 1

erik [133]

Answer:

$\mathbf{(\overline x , \overline y ) = (\dfrac{5}{8}, \dfrac{5}{14})}$

Step-by-step explanation:

Given that:

$y = x^{2/3}$ at y = 0 , x = 1

Then:

Area = $\int^{1}_{0} x^{2/3} \ dx$

Area = $\begin {bmatrix} \dfrac{3}{5}x^{5/3} \end {bmatrix} ^1_0$

Area = $\dfrac{3}{5}$

Then:

$\overline x = \dfrac{1}{A} \int^b_a x (f(x) -g(x) ) \ dx$

$\overline x = \dfrac{5}{3} \int^1_0 x (x^{2/3} -0 ) \ dx$

$\overline x = \dfrac{5}{3} \int^1_0 x^{5/3} \ dx$

$\overline x = \dfrac{5}{3} \ [\dfrac{3}{8}x^{8/3}]^1_0$

$\overline x = \dfrac{5}{3} \times \dfrac{3}{8}$

$\overline x = \dfrac{5}{8}$

Similarly;

$\overline y = \dfrac{1}{A} \int^b_a \dfrac{1}{2} \begin{bmatrix} (f(x)^)2 - (g(x))^2 \end {bmatrix} \ dx$

$\overline y = \dfrac{5}{3} \int^1_0 \dfrac{1}{2} \begin{bmatrix} (f(x^{2/3})^2 -0 \end {bmatrix} \ dx$

$\overline y = \dfrac{5}{3} \int^1_0 \dfrac{1}{2} \begin{bmatrix} (x^{4/3} ) \end {bmatrix} \ dx$

$\overline y = \dfrac{5}{3} \begin{bmatrix} \dfrac{1}{2} (x^{7/3} ) \times \dfrac{3}{7} \end {bmatrix} ^1_0$

$\overline y = \dfrac{5}{3} \begin{bmatrix} \dfrac{3}{14} (x^{7/3} ) \end {bmatrix} ^1_0$

$\overline y = (\dfrac{5}{3} \times \dfrac{3}{14} )$

$\overline y = \dfrac{5}{14}$

Thus; $\mathbf{(\overline x , \overline y ) = (\dfrac{5}{8}, \dfrac{5}{14})}$

4 0

3 years ago

The radius of a semicircle is 2 feet. What is the semicircle's diameter?

fomenos

Answer:

11/7 feet

Step-by-step explanation:

Perimeter of a circle = pi

Semicircle would be 1/2 of pi

1/2 × 22/7 × 1

You must divide by one to get the value of 1/2

11/7 is the answer

8 0

3 years ago

Christopher is 5.2 feet tall and his baby sister is 3 3/4 feet tall. How much taller is Christopher than his baby sister?

vladimir1956 [14]

1 9/20 feet or 1.45 feet.

8 0

3 years ago

Read 2 more answers