Help? Statistics...

Mathematics

2 answers:

BartSMP [9]3 years ago

7 0

On your calculator, use the normalcdf() function, enter the Lower Limit, Upper Limit, Mean, and Standard deviation.

The mean and standard deviation are given to you. You want to find "less than 13.5 seconds", meaning that 13.5 is the maximum "Upper Limit" and 0 would be the Lower Limit because we can pretend 0 second is the minimum. Don't worry about negatives, in this scenario, values like "-5 seconds" are impossible.

Enter normalcdf(0, 13.5, 13.56, 2.24) in a calculator and the output result is the answer.

Irina-Kira [14]3 years ago

4 0

Mean = μ =13.56; Standard deviation = σ = 2.24.
Let's consider the Z distribution where μ =0 and σ = 1
(with x = 13.50)
Let's calculate the Z score: Z = (x-μ)/σ .

Z = (13.50 - 13.56)/2.24 → Z = - 0.026785

For Z = -0.02 , P(Z) = 0.4920 OR 49.20%
For Z = -0.03 , P(Z) = 0.4880 OR 48.80%
Then Z (Approx) = [(48.2)+(48.8)]/2 = 49% (approx.)

Then 49% of a runner chosen at random will have a 200-meter time less than 13.5 seconds

You might be interested in

I need help with this...

lisov135 [29]

ln 5
e = ?
x
Keep in mind that y=e and y = ln x are inverse functions of one another.
ln 5
e , we can drop both the "e" and the "ln 5." We are left with 5 (answer).
ln 5
Alternatively, we could take the ln of both sides of y = e

which will result in ln y = (ln 5) ln e. Note that ln e = 1 (these two functions are inverses of one another).

Then we are left with ln y = ln 5. Dropping the "ln" operator from both sides,

y=5 (same as before).

8 0

3 years ago

Xyz^(2) if x=2 y=7 and z=-4

Afina-wow [57]

Answer:

-224

Step-by-step explanation:

xyz^2

(2)(7)(-4)^2

14 x -16

-224

8 0

2 years ago

What is the value of f(x) = 2 • 2^x for f(–2)? Will Give brainliest answer!!!

Sedbober [7]

For f(-2), x will equal -2.

Plug the x-value into the equation:

$2 \times 2^{-2}$

A negative exponent means that the term turns into a fraction, with 1 as the numerator and the positive exponent as the denominator.
Solve 2^(-2):

$2^{-2} = \frac{1}{2^{2}} = \frac{1}{4}$

Solve the problem:

$2 \times \frac{1}{4} = \frac{1}{2}$

f(-2) will equal 1/2.

5 0

3 years ago

josie cast a shadow of 6ft and she is 5 ft 6 in tall. A building cast a shadow of 18 ft at the same time that josie measured her

Debora [2.8K]

Josie's height = 5 ft 6 in. = 5 1/2 ft = 11/2 ft.
Josie's shadow = 6 ft.

Ratio of shadow to height = 6 / 11/2 = 12/11
So, It would be equal to ratio of building's shadow to building's height.

18/x = 12/11
x = 18*11 /12
x = 3*11 / 2
x = 16.5

In short, Your Answer would be 16.5 Feet

Hope this helps!

6 0

3 years ago

Find the measure of angle A.

Ivanshal [37]

Answer:

∠A = 32°

Step-by-step explanation:

Using the tangent ratio in the right triangle

tanA = $\frac{opposite}{adjacent}$ = $\frac{5}{8}$ = 0.625, thus