Consider the following number line. What is the sign of B+A

A stockbroker has kept a daily record of the value of a particular stock over the years and finds that prices of the stock form

amid [387]

Answer:

$12.43

Step-by-step explanation:

Given :

Mean = $8.52

Standard deviation, = $2.38

Stock price which falls beyond 0.05 of the distribution is at the 95th percentile

The 95th percentile distribution has a Pvalue of 1.645 (standard normal table)

We obtain the value of x, with z = 1.645

Using the Zscore relation :

Zscore = (score - mean) / standard deviation

1.645 = (score - 8.52) / 2.38

Cross multiply :

1.645 * 2.38 = score - 8.52

3.9151 = score - 8.52

Score = 8.52 + 3.9151

Score = $12.4351

Stock price beyond 0.05 is $12.43

8 0

3 years ago

Will give brainliest

Galina-37 [17]

The percentage of the radioactive isotope left is 25.0000%.

The half life of a radioactive isotope is the time that will elapse before only half of the number of original isotopes will remain.

Now;

We are told that;

Half life (t1/2) = 55 days

Time taken (t) = 115 days

Ratio of isotope remaining = N/No

Thus;

N/No = (1/2)^t/t1/2

N/No = (1/2)^115/55

N/No = (1/2)^2

N/No =1/4

Hence, the percentage = 1/4 * 100/1 = 25.0000%

Learn more about half life of an isotope:brainly.com/question/16387602

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7 0

2 years ago

A snail can move 1/30 miles in 1/3 hour. How fast does a snail move in miles /hours

bekas [8.4K]

Answer: 1/10 miles/hour

To find how fast a snail moves in miles per hour, we can find the unit rate using a proportion.

The unit rate is the amount per one unit. In this problem, the unit is for one hour. One way to find the unit rate is by using a proportion.

<h2>Proportions</h2>

Proportions look like two fractions set equal to each other with a missing variable to solve.

<h3>State our variables</h3>

let <em>x</em> be the number of miles per hour

<h3>Write a proportion</h3>

The first fraction has a number for the numerator (top) and denominator (bottom), because the question gives us the information. The second fraction has a missing value, <em>x</em>, that we are solving for. We can write <em>x</em> in the numerator.

$\displaystyle{\frac{\frac{1}{30}\ mi}{\frac{1}{3}\ hr} = \frac{x\ mi}{1\ hr}}$

<h2>Solve</h2>

We can solve by finding the scale factor. The scale factor is the number we can multiply the numerator by to find <em>x</em>.

<h3>Find the scale factor</h3>

Start with the proportion.

$\displaystyle{\frac{\frac{1}{30}\ mi}{\frac{1}{3}\ hr} = \frac{x\ mi}{1\ hr}}$

To find the scale factor,

Take the denominator from the fraction with a variable: $1\ hr$
Take the denominator from the fraction that has no variable: $\frac{1}{3}\ hr$
Divide step 1 by step 2 and solve: $1\ hr\ \div\ \frac{1}{3}\ hr = 3$

Our scale factor is <u>3</u>.

<h3>Solve for x</h3>

We can find <em>x</em> by multiplying the numerator in the first fraction by the scale factor. This is because <em>x</em> is also in the numerator.

$\displaystyle{\frac{\frac{1}{30}\ mi}{\frac{1}{3}\ hr} = \frac{(\frac{1}{30}\ mi)*3}{1\ hr}}$