A student ran out of time on a multiple choice exam and randomly guessed the answers for two problems. Each problem had 5 answer choices - a, b, c, d, e- and only one correct answer. What is the probability that she answered neither of the problems correctly? Do not round your answer. (If necessary, consult a list of formulas.)​

Answer:

mean life = 8264.5 s

Step-by-step explanation:

k = - 0.000121

The relation is given by

[tex]m = mo e^{kt}[/tex]

Now, the mean life is the life time for which the sample retains.

The mean life is the reciprocal of the decay constant.  

The relation between the mean life and the decay constant is

[tex]\tau =\frac{1}{k}\\\\\tau = \frac{1}{0.000121} = 8264.5 seconds[/tex]

Answer:

£1054.729

Step-by-step explanation:

To find compound interest you need to use the equation 1000(1.027)^x.

To find the interest rate (1.027):

100 + 2.7 = 102.7

102.7 / 100 = 1.027

The value of x is the amount of months if no payment is made in this situation, so 2 would be the x value for this problem.

Hope this helps!  

Option C

SOLUTION:

We need to find the value of B - CF

First find the value CF:

[tex]CF=\left[\begin{array}{ccc}12&0&1.5\\1&-6&7\\\end{array}\right] \left[\begin{array}{ccc}-2&0\\0&8\\2&1\end{array}\right][/tex]

[tex]CF=\left[\begin{array}{ccc}12(-2)+0 *0+1.5*2&12*0+0.8+1.5*1\\1*(-2)+(-6)*0+7.2&1*0+(-6)*8+7.1\\\end{array}\right][/tex]

[tex]CF=\left[\begin{array}{ccc}-21&1.5\\12&-41\\\end{array}\right][/tex]

Now find value of B - CF:

[tex]B-CF=\left[\begin{array}{ccc}2&8\\6&3\\\end{array}\right] -\left[\begin{array}{ccc}-21&1.5\\12&-41\\\end{array}\right][/tex]

[tex]B-CF=\left[\begin{array}{ccc}23&6.5\\-6&44\\\end{array}\right][/tex]

∴ the value of B - CF is [tex]\left[\begin{array}{ccc}23&6.5\\-6&44\\\end{array}\right][/tex]

I hope this helps....

Answer:

mapping an area

Step-by-step explanation:

One situation and probably the most common is mapping an area. Graphs are great for dividing a geographical location into various sections and creating a model representation of the area. The graph itself allows for specific directions to be shared using the x and y coordinates on the graph. The same applies for finding the midpoint of a line segment. For example, this is useful if you were trying to find a place to meetup with a friend that is an equal distance from where you are and from where your friend is currently located. Therefore, allowing you to meetup at the midpoint.

9514 1404 393

Answer:

  6,364.8 lb

Step-by-step explanation:

The centroid of the plate is its center, so is 1.5 ft above the bottom of the pool, or 8.5 ft below the surface. The area of the plate is (3 ft)(4 ft) = 12 ft². Then the fluid force is ...

  (62.4 lb/ft³)(8.5 ft)(12 ft²) = 6,364.8 lb

Answer:

x = 22

Step-by-step explanation:

In order to solve this, we need to understand that in an isosceles triangle the two angles that are located at its base are equal to each other.

base - (the side that is not one of the two sides that are equivalent to each other)

Knowing this we can see that ∠ACB will equal ∠BAC, therefore ∠ACB will be equal to x°. Since the sum of all inner angles of a triangle is equal to 180°, we can make the following equation...

x° + x° + (3x + 70)° = 180°

2x° + 3x° + 70° = 180°

5x° = 180° - 70°

5x° = 110°

x° = 110° / 5

x° = 22°

x = 22

Therefore, x = 22.

Answer:

0.65m

Step-by-step explanation:

28cm is equal to 0.28m

37/100 is 37% of a metre so 0.37m

0.28 + 0.37 = 0.65m

Answer:

It would be 6300000. I can't write this in standard form.

Step-by-step explanation:

Answer:

6.3 x 10^6

Step-by-step explanation:

Answer:

16 cm

Step-by-step explanation:

4 + 4 + 3 + 5 = 16

The = sign means that B (which is 4 cm) is equal to D (which had no number)

And because it says that B = D (with the squiggly line (or a tilde)) And the L's (which means that the letters represent an angle) All you have to do is add the numbers together, and you get 16.

Sorry if I explained it badly, you at least got the answer.

(And also, if I'm wrong, please tell me.)

Answer:

P = 32 cm

Step-by-step explanation:

Im just putting the right answer up so you don't accidentally put in the wrong one.

9514 1404 393

Answer:

  (c)  2^r = a

Step-by-step explanation:

The relationship between log forms and exponential forms is ...

  [tex]\log_2(a)=r\ \Leftrightarrow\ 2^r=a[/tex]

__

Additional comment

I find this easier to remember if I think of a logarithm as being an exponent.

Here, the log is r, so that is the exponent of the base, 2.

This equivalence can also help you remember that the rules of logarithms are very similar to the rules of exponents.

Answer: Choice C)  [tex]2^r = a[/tex]

This is the same as writing 2^r = a

==========================================================

Explanation:

Assuming that '2' is the base of the log, then we'd go from [tex]\log_2(a) = r[/tex] to [tex]2^r = a[/tex]

In either equation, the 2 is a base of some kind. It's the base of the log and it's the base of the exponent.

The purpose of logs is to invert exponential operations and help isolate the exponent. A useful phrase to help remember this may be: "if the exponent is in the trees, then we need to log it down".

The general rule is that [tex]\log_b(y) = x[/tex] converts to [tex]y = b^x[/tex] and vice versa.

Answer:

Part 1)

10,000 different numbers.

Part 2)

A) 1 in 10,000.

Step-by-step explanation:

Part 1)

Since there are four digits and there are ten choices for each digit (0 - 9) and digits can be repeated, then we will have:

[tex]T=\underbrace{10}_{\text{Choices For First Digit}}\times\underbrace{10}_{\text{Second Digit}}\times\underbrace{10}_{\text{Third Digit}}\times \underbrace{10}_{\text{Fourth Digit}} = 10^4=10000[/tex]

Thus, 10,000 different numbers are possible.

Part 2)

Since there 10,000 different tickets possible, the chance of one being the correct combination will be 1 in 10,000.

This is equivalent to 0.0001 or a 0.01% chance of winning.

Answer:

2424.5

904.16

Step-by-step explanation:

the mean = ∑frequency /n

∑f = 5+17+36+115+125+81+47+45+22+7 = 500

∑xf = 1212250

∑x²f = 3347037625

sample mean = 1212250/500

= 2424.5

variance = 1/500-1[3347037625 - 1212250²]

= 815710.02

standard deviation is = √variance

standard deviation = √815710.02

= 904.16

Answer:

Andres

why?

Because he is median salary for cpa

Answer:

yes , This is an example of the associative property.

Step-by-step explanation:

Answer:

Most Likely A, 5.5 Miles

Step-by-step explanation:

However the question doesn't make sense as the logical answer is simply 5 miles, but the safest choice is 5.5

Hi there!

[tex]\large\boxed{9(x - 1)^{2}}[/tex]

9x² - 18x + 9

We can begin by factoring out a 9 from each term:

9(x² - 2x + 1)

Now, find two terms that add up to -2 and equal 1 when multiplied. We get:

9(x - 1)(x - 1)

Or:

9(x - 1)²

Answer:

The ocean surface is at 0 ft elevation. A diver is underwater at a depth of 138 ft. In this area, the ocean floor has a depth of 247 ft.

Step-by-step explanation:

Answer:

The answer is 32 divided by 4

Step-by-step explanation:

Because in each box there is 4. There are 8 ovals all together. So 8×4, you get 32 and divide it by the number of squares in an oval which is 4

Answer:

the answer is 32 divided by 4=8

Step-by-step explanation:

because when you look at the ovals there's eight ovals and in side there's four squares..

HOPE THIS HELPS!!!!!

Answer:

45 mph

Step-by-step explanation:

This is a really good question to know the answer to. It is tricky and a bit indirect (which means you have to find something else before you can find the speed of the car.)

Let's keep track of what he does in the time allotted.

How far does Joe go in 5 minutes? That's the amount of time he's on the road before she is.

convert 5 minutes into hours. 5 minutes * 1 hour / 60 minutes = 1/12 of an hour

d = r*t

r = 30 km/hour

t = 1/12 hour

d = 30 km/hr * 1/12 hour = 2.5 km

Now she's about to start. She wants to catch him in 10 minutes

d = r*t

r = x mph

t = 10 minutes = 10 minutes * 1 hour * 60 minutes = 1/6 of an hour.

How far does he go in the 10 minute time?

d = 30 * 1/6 = 5 km

What is his total distance

5 km + 2.5 km = 7.5 km

Finally how fast does she need to go to catch him

d = 7.5 km

r = ?   This is what you are trying to find

t = 1/6 of an hour

d = r*t

7.5 km = r * (1/6)hour             divide by 1/6 hour

7.5 km // 1/6 hour = r

r = 7.5 * 6 = 45 mph

Answer:

(73.845 ; 76.155) ;

(41.633 ; 48.367) ;

1.273 ;

C. With 99% confidence, the mean width of all widgets is between 11.8 and 20.4. ;

1.717

Step-by-step explanation:

1.)

Given :

Mean, xbar = 75

Sample size, n = 24

Sample standard deviation, s = 3.3

α = 90%

Confidence interval = mean ± margin of error

Margin of Error = Tcritical * s/√n

Tcritical at 90% ; df = 24 - 1 = 23

Tcritical = 1.714

Margin of Error = 1.714 * 3.3/√24 = 1.155

Confidence interval = 75 ± 1.155

Confidence interval = (73.845 ; 76.155)

2.)

Given :

Mean, xbar = 45

Sample size, n = 37

Sample standard deviation, s = 10.1

α = 95%

Confidence interval = mean ± margin of error

Margin of Error = Tcritical * s/√n

Tcritical at 95% ; df = 37 - 1 = 36

Tcritical = 2.028

Margin of Error = 2.028 * 10.1/√37 = 3.367

Confidence interval = 45 ± 3.367

Confidence interval = (41.633 ; 48.367)

3.)

Given :

Mean, xbar = 37

Sample size, n = 30

Sample standard deviation, s = 4.1

α = 90%

Margin of Error = Tcritical * s/√n

Tcritical at 90% ; df = 30 - 1 = 29

Tcritical = 1.700

Margin of Error = 1.700 * 4.1/√30 = 1.273

5.)

Sample size, n = 23

Confidence level, = 90%

df = n - 1 ; 23 - 1 = 22

Tcritical(0.05, 22) = 1.717

Solution :

Given :

[tex]f(x) = \left\{\begin{matrix}\frac{1}{450}(x^2-x) & \text{if } 6 < x < 12 \\ 0 & \text{otherwise}\end{matrix}\right.[/tex]

1. Cumulative distribution function

[tex]$P(X \leq x) = \int_{- \infty}^x f(x) \ dx$[/tex]

              [tex]$=\int_{- \infty}^6 f(x) dx + \int_{6}^x f(x) dx $[/tex]

             [tex]$=0+\int_6^x \frac{1}{450}(x^2-x) \ dx$[/tex]

             [tex]$=\frac{1}{450} \int_6^x (x^2-x) \ dx$[/tex]

             [tex]$=\frac{1}{450}\left[\frac{x^3}{3}-\frac{x^2}{2}\right]_6^x$[/tex]

             [tex]$=\frac{1}{450}\left[ \left( \frac{x^3}{3} - \frac{x^2}{2}\left) - \left( \frac{6^3}{3} - \frac{6^2}{2} \right) \right] $[/tex]

            [tex]$=\frac{1}{450}\left[\frac{x^3}{3} - \frac{x^2}{2} - 54 \right]$[/tex]

2.  Mean [tex]$E(x) = \int_{- \infty}^{\infty} \ x \ f(x) \ dx$[/tex]

                       [tex]$=\int_{6}^{12}x . \left( \frac{1}{450} \ (x^2-x)\right)\ dx$[/tex]

                     [tex]$=\frac{1}{450} \int_6^{12} \ (x^3 - x^2) \ dx$[/tex]

                     [tex]$=\frac{1}{450} \left[\frac{x^4}{4} - \frac{x^3}{3} \right]_6^{12} \ dx$[/tex]

                     [tex]$=\frac{1}{450} \left[ \left(\frac{(12)^4}{4} - \frac{(12)^3}{3} \right) - \left(\frac{(6)^4}{4} - \frac{(6)^3}{3} \right) $[/tex]

                     [tex]$=\frac{1}{450} [4608 - 252]$[/tex]

                    = 17.2857

Answer:

1.25. It would be 1.25 if ur just talking about dividing in general which is pretty tough

Answer:

\dfrac54=-4c+\dfrac14 4 5 ​ =−4c+ 4 1 ​ start fraction, 5, divided by, 4, end fraction, equals, minus, 4, c, plus, start fraction, 1, divided by, 4, end fraction

Step-by-step explanation:

Step-by-step explanation:

this is the answerI hope it helps

Answer:

3/4

Step-by-step explanation:

Let a be the length of the shorter line segment and b be the length of the longer line segment.

Since the length of the line segment is l, we have that the length of the line segment equals length of shorter line segment + length of longer line segment.

So, l = a + b

Since we require that the longer line segment be at least three times longer than the shorter line segment, we have that b = 3a

So, l = a + b

l = a + 3a

l = 4a

The probability that the shorter line segment will be a(or 3 times shorter than b) is P(a) = length of shorter line segment/length of line segment = a/l

Since l = 4a.

a/l = 1/4

So, P(a) = 1/4

The probability that a will be less than 3 times shorter that b is P(a ≤ 1) = P(0) + P(a) = 0 + 1/4 = 1/4

The probability that b will be 3 times or more greater than a is thus P(b ≥ 3) = 1 - P(a ≤ 1) = 1 - 1/4 = 3/4

Answer:

y = (-x)^3 - 4

Step-by-step explanation:

Ok, for the function:

y = x^3

When x = 0, we have:

y = 0^3  = 0

So the original graph passes through the point (0, 0)

If we look at the given graph, we can see that the y-intercept (the value of y when x = 0) is:

y = -4

So, this is the graph of y = x^3 moved down 4 units.

You can also see that the graph goes downward as x increases (and up as x decreases) while for the function:

y = x^3

as x increases, we should see that y also increases.

Then we have a reflection across the x-axis.

Ok, now let's describe a vertical shift.

For a general function f(x), a vertical shift of N units is written as:

g(x) = f(x) + N

if N is positive, the shift is upwards

if N is negative, the shift is downwards.

And for a function f(x), a reflection across the x-axis is written as:

g(x) = - f(x)

Here we first apply the reflection across the x-axis, so we get:

g(x) = -f(x)

now we apply the shift 4 units downwards

g(x) = - f(x) - 4

replacing f(x) by our function, x^3

we get:

g(x) = -x^3 - 4

And because of the odd power, we can write:

-x^3 = (-x)^3

Then the function is:

g(x) = (-x)^3 - 4

The correct option is the last one.

y = (-x)^3 - 4

Step-by-step explanation:

here is the answer to your question