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3 years ago

30. The average age of 20 boys is 15.

Mathematics

2 answers:

Alex787 [66]3 years ago

6 0

Answer:

D. 300 years

Step-by-step explanation:

Mean = $\frac{sum of observations}{no. of observations\\}$

Here we know the mean which is 15 and the number which is 20

Total age = 15 × 20

Total Age = 300 years

Simora [160]3 years ago

4 0

Answer:

D. 300 Years is the correct answer.

Step by Step Explanation:

20×15= 300

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the slope of a line passing through h (-2, 5) is -3/4. Which ordered pair represents a point on this line?

rosijanka [135]

Answer:

Step-by-step explanation:

Calculate the slope of the given points with the point (- 2, 5 )

If the slope is - $\frac{3}{4}$ then the point is on the line

Calculate slope m using the slope formula

m = $\frac{y_{2}-y_{1} }{x_{2}-x_{1} }$

with (x₁, y₁ ) = (- 2, 5) and (x₂, y₂ ) = (6, - 1)

m = $\frac{-1-5}{6+2}$ = $\frac{-6}{8}$ = - $\frac{3}{4}$ ← point (6, - 1) is on the line

Repeat with (x₁, y₁ ) = (- 2, 5 ) and (x₂, y₂ ) = (2, 8)

m = $\frac{8-5}{2+2}$ = $\frac{3}{4}$ ← point (2, 8) is not on the line

Repeat with (x₁, y₁ ) = (- 2, 5) and (x₂, y₂ ) = (- 5, 1)

m = $\frac{1-5}{-5+2}$ = $\frac{-4}{-3}$ = $\frac{4}{3}$ ← point (- 5, 1) is not on the line

Repeat with (x₁, y₁ ) = (- 2, 5) and (x₂, y₂ ) = (1, 1)

m = $\frac{1-5}{1+2}$ = - $\frac{4}{3}$ ← point (1, 1) is not on the line

Thus the point on the line is (6, - 1 ) → A

4 0

3 years ago

A machine in a chocolate factory is set to squirt out a predetermined amount of molten chocolate. When the machine is set to x,

frez [133]

Answer:

Sorry I need Points but I also need help

Step-by-step explanation:

3 0

3 years ago

Suppose that a recent poll of American households about car ownership found that for households with a car, 39% owned a sedan, 3

Dimas [21]

Let the total number of cars = 100

Total of sedan, van and sports cars = 39+33+7 = 79

Number of other cars = 100 - 79 = 21.

Let A be the event of owning a sedan,

B be the event of owning a van and

C be the event of owning a sports car.

D be the event of owning other cars.

Then, $p(A) = \frac{39}{100}$

$p(B)=\frac{33}{100}$ and

$p(C) = \frac{7}{100}$

$p(D) = \frac{21}{100}$

Now,

p(non selection of van) = p(A ∪ C ∪ D)

= p(A) + p(C) + p(D)

$=\frac{39}{100} +\frac{7}{100} +\frac{21}{100}$

$=\frac{67}{100}$

= 0.67

The probability of none of the three selections would be a van is:

0.67 × 0.67 × 0.67

= 0.300763

=0.301

Hence, the correct option is (D).

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3 years ago

What is the vertex form of y=x^2-6x+6

andrezito [222]

Answer:

y = (x - 3)² - 3

Step-by-step explanation:

The equation of a parabola in vertex form is

y = a(x - h)² + k

where (h, k) are the coordinates of the vertex and a is a multiplier

To obtain this form use the method of completing the square

add/subtract (half the coefficient of the x- term )² to x² - 6x

Given

y = x² - 6x + 6

= x² + 2(- 3)x + 9 - 9 + 6

= (x - 3)² - 3 ← in vertex form

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Tomtit [17]

Answer:

Step-by-step explanation:

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3 years ago

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