Help Me Please!!!!!!!!<br> f(x)= 2x^{2} -6x+11,D={x|x}

Layla calculates the mean of the ages of 10 students on her bus, and she discovers the average(mean) age is 12.8. What will happ

Leni [432]

Answer:

The mean will increase

Step-by-step explanation:

6 0

2 years ago

A building is 5 feet tall. the base of the ladder is 8 feet from the building. how tall must a ladder be to reach the top of the

iris [78.8K]

The ladder must be 9.4 ft to reach the top of the building

Here, we want to get the length of the ladder that will reach the top of the building

Firstly, we need a diagrammatic representation

We have this as;

As we can see, we have a right triangle with the hypotenuse being the length of the ladder

We simply will make use of Pythagoras' theorem which states that the square of the hypotenuse is equal to the sum of the squares of the two other sides

Thus, we have;

$\begin{gathered} x^2=5^2+8^2 \\ x^2=\text{ 25 + 64} \\ x^2\text{ = 89} \\ x=\text{ }\sqrt[]{89} \\ x\text{ = 9.4 ft} \end{gathered}$

5 0

1 year ago

What is the value of x?

Lerok [7]

Answer:

3√2

Step-by-step explanation:

The hypotenuse of an isosceles right triangle is √2 times the side length.

x = 3√2

_____

All these triangles are similar, so the ratio of hypotenuse to leg is the same for all.

hypotenuse/leg = x/3 = (3+3)/x

x² = 3·6 = 3²·2 . . . . cross multiply (identify square factors)

x = 3√2 . . . . . take the square root

7 0

3 years ago

The fracture strength of tempered glass averages 14 (measured in thousands of pounds per square inch) and has standard deviation

Wewaii [24]

Answer:

0.1587 = 15.87% probability that the average fracture strength of 100 randomly selected pieces of this glass exceeds 14.2.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .