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3 years ago

PLEASE HELP

Mathematics

1 answer:

arsen [322]3 years ago

6 0

Answer:

Answer is b) 20.

Step-by-step explanation:

Mean is 0.43 kg.

0.43+0.1+0.1= 0.45

0.45 is two standard deviation above.

All that are below mean is 50%,

Two standard deviation above is 95%/2=47.5%

50%+47.5% =97.7% are balls that are less than 0.45 kg.

100%-97.7%=2.5% balls that are more than 0.45 kg

2.3%=0.025

800*0.025 = 20 soccer balls weigh more than 0.45 kg

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Given matrix A below, calculate det[A] twice using minors and cofactors

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Answer:

a. 3(16-21) - 4(8-18) +5(7-12) = -15 + 40 - 25 = 0

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3 years ago

For an intramural sports program at a particular college, the time to run one mile is recorded for 200 male students in the prog

Greeley [361]

Answer:

Devon has the lower z-score, so he ran the mile faster relative to his gender.

Step-by-step explanation:

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Who ran the mile faster relative to their gender?

The lower the percentile of time ran, the faster. So whoever has the lower z-score ran the mile faster.

Devon

His best time to run the mile is 6.6 minutes.

These times are approximately normal with mean 8 minutes and standard deviation 1 minute.

We have to find Z when $X = 6.6, \mu = 8, \sigma = 1$ . So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{6.6 - 8}{1}$

$Z = -1.4$

Kendall

Her best time to run the mile is 5.7 minutes.

These times are approximately normal with mean 7.5 minutes and standard deviation 2 minutes.

We have to find Z when $X = 5.7, \mu = 7.5, \sigma = 2$ . So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{5.7 - 7.5}{2}$

$Z = -0.9$

Devon has the lower z-score, so he ran the mile faster relative to his gender.

3 0

3 years ago

Answer problem below

garri49 [273]

Answer:

A = 2, B = 1, C = 28

Step-by-step explanation:

Find the slope of the line AB.

<u>The slope:</u>

m = (11 - 9)/(11 - 7) = 2/4 = 1/2

Since the altitude is perpendicular to AB, it has a slope of -2.

The line with the slope of -2 and passes through point C(6, 16).

<u>Use point-slope equation to find the line:</u>

y - 16 = -2(x - 6)
y - 16 = -2x + 12
y + 2x = 16 + 12
2x + y = 28

A = 2, B = 1, C = 28

7 0

3 years ago

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Answer:

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2 years ago

Si consideras como base uno de los rectángulos de dimensiones de 5cm y 3cm ¿cuanto mide la altura de ese prisma?

Vinvika [58]

Respuesta:

h = V / 15

Explicación paso a paso:

El volumen de un prisma rectangular se calcula usando la relación:

Largo ancho alto

Donde, largo y ancho son la dimensión de la base

Por eso,

Volumen = Base * altura

Volumen = (5 cm * 3 cm) * altura

De la pregunta, no se da el volumen, por lo tanto, tomamos el volumen como V en otro para calcular la altura, h

V = 15h

Divide ambos lados entre 15

V / 15 = 15h / 15

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