I need help to understand the answer step by step directions

The life in hours of a biomedical device under development in the laboratory is known to be approximately normally distributed.

bearhunter [10]

Answer:

Kindly check explanation

Step-by-step explanation:

H0 : μ = 5500

H1 : μ > 5500

The test statistic assume normal distribution :

Test statistic :

(Xbar - μ) ÷ s/sqrt(n)

(5625.1 - 5500) ÷ 226.1/sqrt(15) = 2.1429 = 2.143

Pvalue from test statistic :

The Pvalue obtained using the calculator at df = 15 - 1 = 14 is 0.025083

α = 0.05

Since ;

Pvalue < α

0.025083 < 0.05 ; Reject H0

The confidence interval :

Xbar ± Tcritical * s/sqrt(n)

Tcritical at 95% = 1.761 ;

margin of error = 1.761 * 226.1/sqrt(15) = 102.805

Lower boundary : (5625.1 - 102.805) = 5522.295

(5522.295 ; ∞)

The hypothesized mean does not occur within the constructed confidence boundary. HENCE, there is significant eveidbce to support the claim that the true mean life of a biomedical device is greater than 5500

4 0

3 years ago

What is the area of trapezoid ABCD? A(-2,2) B(2,5) C(11,-7) D(1,-2)

Ksenya-84 [330]

Answer:

50 sq. units

Step-by-step explanation:

Join one diagonal of the trapezoid ABCD.

Assume that AC is the diagonal.

So, Area of the trapezoid = Area of Δ ABC + Area of Δ CAD.

Now, coordinates of A(-2,2), B(2,5), C(11,-7) and D(1,-2) are given.

We know, that three vertices of a triangle are $(x_{1},y_{1} )$ , $(x_{2},y_{2} )$ and $(x_{3},y_{3} )$ respectively, then the area of the triangle will be given by

$\frac{1}{2} |x_{1}(y_{2}-y_{3})+x_{2}(y_{3}-y_{1})+ x_{3}(y_{1}-y_{2} ) |$

Hence, area of Δ ABC will be

$\frac{1}{2} |-2(5-(-7))+2(-7-2)+11(2-5)|= 37.5$ sq units.

Again, area of Δ CAD will be

$\frac{1}{2} |11(2-(-2))-2(-2-(-7))+1(-7-2)|= 12.5$ sq units.

Therefore, the area of the trapezoid ABCD will be (37.5 + 12.5) = 50 sq, units. (Answer)

4 0

4 years ago

Sin(-136°) = _____. sin (-316)° -sin 44° -sin 316° -cos 44°

erastova [34]

Answer:

- cos 44°

Step-by-step explanation:

I think the correct option is "D"

Hope it helps

8 0

3 years ago

Select the correct answer for each statement. (k+2, k+3 , k+4) or (k+10, k+12, k+14) will yield consecutive odd integers. (k+6,

almond37 [142]

Answer:

Step-by-step explanation:

one

The only really certain way of getting an odd integer is to do 2k + 1. Therefore the answer should be something like 2k+1, 2k+3, 2k + 5

The best I can do for the first one is to assume that k is odd and that the answer is k + 10, k+12, k+14, but I would ask your instructor if this is merely the best answer out of a poor lot or if the question really has no answer.

Two things should be noted.

1. k has to be odd.

2. The first choice has to give consecutive integers because what is added on is 2 3 and 4. Those numbers are consecutive.

Two

k+1, k+2, k+3. See point 2 above. k is a constant and any number. 1,2,3 are consecutive so the results are consecutive. Even if k < 0 the numbers will be consecutive.

k= - 10

k+1 = - 9

k+2 = -8

k+3 = - 7

These are consecutive.

Your first choice will give either consecutive odd or even numbers depending on what k is.

If k = even, then k+6, k+ 8, k+10 will all be even.

If k = odd then the givens will be odd.

4 0

4 years ago

Read 2 more answers

14.

svp [43]

Answer:

D. y= 2(x + 3)^2 - 3

Step-by-step explanation:

Rewrite in vertex form and use this form to find the vertex

( h , k ) . ( 3 , − 3 )

Rewrite in vertex form and use this form to find the vertex

( h , k ) . ( 3 , 3 )

Rewrite in vertex form and use this form to find the vertex

( h , k ) . ( − 3 , − 3 )

Rewrite in vertex form and use this form to find the vertex

( h , k ) . ( − 3 , − 3 )

7 0

3 years ago