All categories

3 years ago

2

Mathematics

1 answer:

Pachacha [2.7K]3 years ago

4 0

Answer:

New area: 12ft^2

Step-by-step explanation:

1/3 of 9 is 3

1/3 of 12 is 4

Area = l x w

so 3 x 4 = 12

You might be interested in

An automobile company wants to determine the average amount of time it takes a machine to assemble a car. A sample of 40 times y

aksik [14]

Answer:

A 98% confidence interval for the mean assembly time is [21.34, 26.49] .

Step-by-step explanation:

We are given that a sample of 40 times yielded an average time of 23.92 minutes, with a sample standard deviation of 6.72 minutes.

Firstly, the pivotal quantity for finding the confidence interval for the population mean is given by;

P.Q. = $\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }$ ~ $t_n_-_1$

where, $\bar X$ = sample average time = 23.92 minutes

s = sample standard deviation = 6.72 minutes

n = sample of times = 40

$\mu$ = population mean assembly time

Here for constructing a 98% confidence interval we have used a One-sample t-test statistics because we don't know about population standard deviation.

So, a 98% confidence interval for the population mean, $\mu$ is;

P(-2.426 < $t_3_9$ < 2.426) = 0.98 {As the critical value of z at 1% level

of significance are -2.426 & 2.426}

P(-2.426 < $\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }$ < 2.426) = 0.98

P( $-2.426 \times {\frac{s}{\sqrt{n} } }$ < ${\bar X-\mu}$ < $2.426 \times {\frac{s}{\sqrt{n} } }$ ) = 0.98

P( $\bar X-2.426 \times {\frac{s}{\sqrt{n} } }$ < $\mu$ < $\bar X+2.426 \times {\frac{s}{\sqrt{n} } }$ ) = 0.98

98% confidence interval for $\mu$ = [ $\bar X-2.426 \times {\frac{s}{\sqrt{n} } }$ , $\bar X+2.426 \times {\frac{s}{\sqrt{n} } }$ ]

= [ $23.92-2.426 \times {\frac{6.72}{\sqrt{40} } }$ , $23.92+2.426 \times {\frac{6.72}{\sqrt{40} } }$ ]

= [21.34, 26.49]

Therefore, a 98% confidence interval for the mean assembly time is [21.34, 26.49] .

7 0

2 years ago

Question 5

DochEvi [55]

7383838hdueheheheueuwjhwwhjwiw82828182828

7 0

1 year ago

Help again <3 ty i will very much appreciate it

krok68 [10]

Answer:

5√3 is the simplified radical expression.

3 0

3 years ago

5×-3(4×-8)=-11 helppppppp

Damm [24]

5x - 3(4x-8) = -11

5x - 12x + 24 = -11

-7x + 24 = -11

-7x = - 35

x = 5

4 0

2 years ago

(10x -20) (6x + 8)° what is the value of x

Hoochie [10]

Answer:

X=12

Step-by-step explanation:

Add the two equations together and equate them to 180 due to the geometrical reason that angles on a straight line add up to 180.

10X-20+6X+8=180 (collect like terms)

10X+6X=180-8+20

16X=192 (Divide both sides by 16)

X=12

Hope that helps :)

7 0

2 years ago