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3 years ago

The times for completing one circuit of a bicycle course are normally distributed with

Mathematics

1 answer:

Sonja [21]3 years ago

4 0

Answer:

The answer is 76.9 rounded or rounds.

Step-by-step explanation:

Solution

Given that:

Mean = μ = 72.5

Standard deviation = σ = 6.5

Now

By applying the standard normal table we have the following:

P(Z < z) = 75%

= P(Z < z)

= 0.75

Thus

z =0.67 by using the standard normal z table

Applying the z-score formula we have:

x = z * σ + μ

x = 0.67*6.5+72.5

x= 76.855 ≈ 76.9

Therefore the cutoff time is 76.9 rounds.

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The number of guests per month at a large resort is given in the table below, where f(x) is the number of guests, in hundreds, x

Solnce55 [7]

X = 0 ; y = 10 ; 10 = a(0) + b(0) + c
c = 10

x=2 ; y = 15 ; 15 = a(4) + b(2) + 10 ; 5 = 4a+2b
x=4 ; y=18 ; 18 = a(16) + b(4) + 10 ; 8 = 16a + 4b

2(5) = (4a+2b)2
-
<u> 8 = 16a + 4b
</u> 2 = -8a

a = -0.25

b = 2

y = (1/4)x^2 + 2x + 10 ; 4y = x^2 + 8x + 40

8 0

3 years ago

Read 2 more answers

14=6n+6-2n solve for n

Anika [276]

Answer:

n=2

Step-by-step explanation:

14=6n+6-2n

Combine like terms

14 = 4n+6

Subtract 6 from each side

14 -6 = 4n+6-6

8 = 4n

Divide by 4

8/4 = 4n/4

2 =n

8 0

3 years ago

Read 2 more answers

Determine the most precise name for ABCD (parallelogram, rhombus, rectangle, or square). Explain how you determined your answer.

Sonja [21]

<h3>Answer: Rhombus</h3>

======================================================

Reason:

Let's find the distance from A to B. This is equivalent to finding the length of segment AB. I'll use the distance formula.

$A = (x_1,y_1) = (3,5) \text{ and } B = (x_2, y_2) = (7,6)\\\\d = \sqrt{(x_1 - x_2)^2 + (y_1 - y_2)^2}\\\\d = \sqrt{(3-7)^2 + (5-6)^2}\\\\d = \sqrt{(-4)^2 + (-1)^2}\\\\d = \sqrt{16 + 1}\\\\d = \sqrt{17}\\\\d \approx 4.1231\\\\$

Segment AB is exactly $\sqrt{17}$ units long, which is approximately 4.1231 units.

If you were to repeat similar steps for the other sides (BC, CD and AD) you should find that all four sides are the same length. Because of this fact, we have a rhombus.

-------------------------

Let's see if this rhombus is a square or not. We'll need to see if the adjacent sides are perpendicular. For that we'll need the slope.

Let's find the slope of AB.

$A = (x_1,y_1) = (3,5) \text{ and } B = (x_2,y_2) = (7,6)\\\\m = \frac{y_{2} - y_{1}}{x_{2} - x_{1}}\\\\m = \frac{6 - 5}{7 - 3}\\\\m = \frac{1}{4}\\\\$

Segment AB has a slope of 1/4.

Do the same for BC

$B = (x_1,y_1) = (7,6) \text{ and } C = (x_2,y_2) = (6,2)\\\\m = \frac{y_{2} - y_{1}}{x_{2} - x_{1}}\\\\m = \frac{2 - 6}{6 - 7}\\\\m = \frac{-4}{-1}\\\\m = 4\\\\$

Unfortunately the two slopes of 1/4 and 4 are not negative reciprocals of one another. One slope has to be negative while the other is positive, if we wanted perpendicular lines. Also recall that perpendicular slopes must multiply to -1.

We don't have perpendicular lines, so the interior angles are not 90 degrees each.

Therefore, this figure is not a rectangle and by extension it's not a square either.

The best description for this figure is a <u>rhombus</u>.

4 0

2 years ago

Read 2 more answers

Please help me, I will give brainliest! :D

solong [7]

Answer:

Sorry i dont know but need the points

Step-by-step explanation:

3 0

3 years ago

Work out the size of the interior angle of a regular 18-sided polygon.

qaws [65]

Answer:

160°

Step-by-step explanation:

The formula below gives the measure of an interior angle of a regular polygon of n sides.

[(n - 2)180]/n

[(18 - 2)180]/18

16(10)

160

Answer: 160°

4 0

3 years ago