Find the ratio of x to y if 7/x = 5/y. Help me!!!!

The probability that a lab specimen contains high levels of contamination is 0.10. Five samples are checked, and the samples are

raketka [301]

Answer:

(a) 0.59049 (b) 0.32805 (c) 0.40951

Step-by-step explanation:

Let's define

$A_{i}$ : the lab specimen number i contains high levels of contamination for i = 1, 2, 3, 4, 5, so,

$P(A_{i})=0.1$ for i = 1, 2, 3, 4, 5

The complement for $A_{i}$ is given by

$A_{i}^{$c$}$ : the lab specimen number i does not contains high levels of contamination for i = 1, 2, 3, 4, 5, so

P( $A_{i}^{$c$}$ )=0.9 for i = 1, 2, 3, 4, 5

(a) The probability that none contain high levels of contamination is given by

P( $A_{1}^{$c$}$ ∩ $A_{2}^{$c$}$ ∩ $A_{3}^{$c$}$ ∩ $A_{4}^{$c$}$ ∩ $A_{5}^{$c$}$ )= $(0.9)^{5}$ =0.59049 because we have independent events.

(b) The probability that exactly one contains high levels of contamination is given by

P( $A_{1}$ ∩ $A_{2}^{$c$}$ ∩ $A_{3}^{$c$}$ ∩ $A_{4}^{$c$}$ ∩ $A_{5}^{$c$}$ )+P( $A_{1}^{$c$}$ ∩ $A_{2}$ ∩ $A_{3}^{$c$}$ ∩ $A_{4}^{$c$}$ ∩ $A_{5}^{$c$}$ )+P( $A_{1}^{$c$}$ ∩ $A_{2}^{$c$}$ ∩ $A_{3}$ ∩ $A_{4}^{$c$}$ ∩ $A_{5}^{$c$}$ )+P( $A_{1}^{$c$}$ ∩ $A_{2}^{$c$}$ ∩ $A_{3}^{$c$}$ ∩ $A_{4}$ ∩ $A_{5}^{$c$}$ )+P( $A_{1}^{$c$}$ ∩ $A_{2}^{$c$}$ ∩ $A_{3}^{$c$}$ ∩ $A_{4}^{$c$}$ ∩ $A_{5}$ )=5×(0.1)× $(0.9)^{4}$ =0.32805

because we have independent events.

(c) The probability that at least one contains high levels of contamination is

P( $A_{1}$ ∪ $A_{2}$ ∪ $A_{3}$ ∪ $A_{4}$ ∪ $A_{5}$ )=1-P( $A_{1}^{$c$}$ ∩ $A_{2}^{$c$}$ ∩ $A_{3}^{$c$}$ ∩ $A_{4}^{$c$}$ ∩ $A_{5}^{$c$}$ )=1-0.59049=0.40951

6 0

3 years ago

the perimeter of a rectangle is 50 inches the length l is twice the width w. what is the area of the rectangle?? ❗️show work❗️

mr Goodwill [35]

Hey. Let me help you on this one.

In order for us to solve this problem, we will need to set up an equation which we can solve later. I will also be attaching an image with the work shown in case you don't understand my explanation. Make sure to read over it since it will help you with your studies.

We know that the length is twice the width, meaning that $a=2b$ , with "a" standing for length, and "b" standing for width. Now that we have formed an equation for length, we can actually form an equation for perimeter.

$P=2(2b)+2b$

Let's simplify the equation so it's easier and less confusing for us to solve it.

$50=6b$

Let's divide 6 from both sides, thus eliminating all variables except for b on the right side.

$8.3=b$

"3" in 8.3 is repeating. This is very important to remember. Now, we know the width of the triangle. Let's find the length of the triangle so we can then multiply both numbers together and find the area.

$a=8.3*2$
$a=16.6$

"6" in 16.6 is repeating as well. It's crucial to remember as well. We know the values now, meaning that we can find the area of the rectangle.

$S=16.6*8.3$
$S=138.8$

Answer: Area of the rectangle is 138.8 (with 8 repeating).

4 0

4 years ago

Write x ² +6X = -5 in general form

Leto [7]

Answer:

X^2+6x+5=0

Step-by-step explanation:

Ax+By+C=0 is what you follow for getting the general form. In this case, you go from descending order and x^2 is the highest point/degree. Therefore, x^2+6x+5=0. Hope this helps!

6 0

3 years ago

Find the values of m and n that make equation true. <br><br> 8+15i=2m+3ni

Brilliant_brown [7]

gthy67jntgrt67u89i7yu holfcedikjnhfnhtfrolwsfr n/lkjhfwr3n oljfu vikr8hneikoeOPDTE85417

+TE4TE

8 0

3 years ago

What's the chance of NOT rolling a seven using a pair of dice.

Gemiola [76]

Answer:

5/6

Step-by-step explanation:

total possible = 36

Favorable = 6

1 6

6 1

2 4

4 2

3 4

4 3

Part/whole

6/36

= 1/6

NOT = 5/6

7 0

3 years ago