Ask question

Ask question

All categories

2 years ago

5

(HELP!)Coach DeCaro records the cross country runners' times compared to their personal best times. Which runners ran slower tha

n their personal best?

2 answers:

Akimi4 [234]2 years ago

7 0

Answer:

D Is the answer.

Step-by-step explanation:

Good Luck uWu

Alborosie2 years ago

6 0

Answer:

it should be karen and hiroki

karen ran 5.2 seconds slower than her personal best

hiroki ran 11.6 slower than his/her best

You might be interested in

The weight of an adult swan is normally distributed with a mean of 26 pounds and a standard deviation of 7.2 pounds. A farmer ra

Snezhnost [94]

Let $X$ denote the random variable for the weight of a swan. Then each swan in the sample of 36 selected by the farmer can be assigned a weight denoted by $X_1,\ldots,X_{36}$ , each independently and identically distributed with distribution $X_i\sim\mathcal N(26,7.2)$ .

You want to find

$\mathbb P(X_1+\cdots+X_{36}>1000)=\mathbb P\left(\displaystyle\sum_{i=1}^{36}X_i>1000\right)$

Note that the left side is 36 times the average of the weights of the swans in the sample, i.e. the probability above is equivalent to

$\mathbb P\left(36\displaystyle\sum_{i=1}^{36}\frac{X_i}{36}>1000\right)=\mathbb P\left(\overline X>\dfrac{1000}{36}\right)$

Recall that if $X\sim\mathcal N(\mu,\sigma)$ , then the sampling distribution $\overline X=\displaystyle\sum_{i=1}^n\frac{X_i}n\sim\mathcal N\left(\mu,\dfrac\sigma{\sqrt n}\right)$ with $n$ being the size of the sample.

Transforming to the standard normal distribution, you have

$Z=\dfrac{\overline X-\mu_{\overline X}}{\sigma_{\overline X}}=\sqrt n\dfrac{\overline X-\mu}{\sigma}$

so that in this case,

$Z=6\dfrac{\overline X-26}{7.2}$

and the probability is equivalent to

$\mathbb P\left(\overline X>\dfrac{1000}{36}\right)=\mathbb P\left(6\dfrac{\overline X-26}{7.2}>6\dfrac{\frac{1000}{36}-26}{7.2}\right)$
$=\mathbb P(Z>1.481)\approx0.0693$

5 0

3 years ago

How do you simplify 16^2/24^7

quester [9]

Answer:

1/(2¹³·3⁷)

Step-by-step explanation:

16²/24⁷

Factor the terms = (2⁴)²/(8×3)⁷

Apply the Power Rule = 2⁸/(2³×3)⁷

Apply the Power Rule = 2⁸/(2²¹ × 3⁷)

Apply the Quotient Rule = 1/(2¹³·3⁷)

5 0

3 years ago

If you add my number to it's self and add 83 you will get the same number as when you add my number 4 times and subtract 25

Deffense [45]

I think you should put in 53 try that

7 0

3 years ago

Find the base of a traingle with area 20dm² and height 12 1/2dm <br>

AlexFokin [52]

9514 1404 393

Answer:

32 dm

Step-by-step explanation:

Use the formula for the area of a triangle, and solve for the unknown.

A = 1/2bh

200 dm² = 1/2(12.5 dm)b

b = (200 dm²)/(6.25 dm) = 32 dm

The base of the triangle is 32 dm.

3 0

2 years ago

En tres partidos de besisbol de fin de Semana, hubo 125,429 espectadores .La Semana siguiente hubi 86,353 especradores cuantos e

Pavlova-9 [17]

Answer:

211,782

Step-by-step explanation:

Esta pregunta es muy fácil porque Los espectadores en total que presenciaron los seis partidos en total es la suma de ambos.

125,429 en uno lado y 86,353 en uno lado. Y eso es igual

125,429 + 86,353 = 211,782

Los espectadores en total que presenciaron los seis partidos en total es 211,782

8 0

2 years ago