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3 years ago

What is ( 3x - -4 ) + (5 + 4x)

Mathematics

1 answer:

sesenic [268]3 years ago

5 0

It is 7x+9 because Simplify $3x--4$ to 3x+4 and than combine like terms.than simplify

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Han used 1 1/2 gallons of paint to paint 3/5 of a shed. How many gallons of paint will it take to paint the whole shed? write a

PilotLPTM [1.2K]

The answer is 2gallons

7 0

3 years ago

The ages of a random sample of five university professors are 39, 54, 61, 72, and 59. Using this information, find a 99% confide

kondor19780726 [428]

Answer:

99% confidence interval for the population standard deviation = (74.97 , 635.20).

Step-by-step explanation:

We are given that the ages of a random sample of five university professors are 39, 54, 61, 72 and 59. Also, it is provided that the ages of university professors are normally distributed.

So, firstly the pivotal quantity for 99% confidence interval for the population standard deviation is given by;

P.Q. = $\frac{(n-1)s^{2} }{\sigma^{2} }$ ~ $\chi^{2} __n_-_1$

where, s = sample standard deviation

$\sigma$ = population standard deviation

n = sample of university professors = 5

Also, $s^{2}$ = $\frac{\sum (X-\bar X)^{2} }{n-1}$ = 144.5

So, 99% confidence interval for population standard deviation, $\sigma$ is;

P(0.2070 < $\chi^{2} __5_-_1$ < 14.86) = 0.99 {As the table of $\chi^{2}$ at 4 degree of freedom

gives critical values of 0.2070 & 14.86}

P(0.2070 < $\frac{(n-1)s^{2} }{\sigma^{2} }$ < 14.86) = 0.99

P( $\frac{ 0.2070}{(n-1)s^{2} }$ < $\frac{1 }{\sigma^{2} }$ < $\frac{ 14.86}{(n-1)s^{2} }$ ) = 0.99

P( $\frac{ (n-1)s^{2}}{14.86 }$ < $\sigma^{2}$ < $\frac{ (n-1)s^{2}}{0.2070 }$ ) = 0.99

99% confidence interval for $\sigma^{2}$ = ( $\frac{ (n-1)s^{2}}{14.86 }$ , $\frac{ (n-1)s^{2}}{0.2070 }$ )

= ( $\frac{ (5-1) \times 144.5^{2}}{14.86 }$ , $\frac{ (5-1) \times 144.5^{2}}{0.2070 }$ )

= (5620.525 , 403483.092)

99% confidence interval for $\sigma$ = ( $\sqrt{5620.525}$ , $\sqrt{403483.092}$ )

= (74.97 , 635.20)

Therefore, 99% confidence interval for the population standard deviation of the ages of all professors at the university is (74.97 , 635.20).

8 0

4 years ago

There are 400 seats in the Jefferson Middle School auditorium. The students are using 35 of the seats. There are 65 seats being

jolli1 [7]

Answer:

300

Step-by-step explanation:

400 - 35 - 65 = 300

100 seats being used, so 300 seats left unused

(Btw, do you happen to know of a certain Northeast Middle School at all?)

6 0

3 years ago

1A 3-gallon cylindrical water container has a height of 1.5 feet and a radius of 3.5 inches. Nate fills up a 2-gallon jug from t

Sonja [21]

Its height would be at .5 I hoped that helped

3 0

3 years ago

The rectangle shown

Viktor [21]

The answer is C- 20

a^2 + b^2=c^2

5 0

3 years ago