Use function notation to represent each statement. Six hours after it started raining, the amount of rain was 37 millimeters.

Sara buys a sweater at a department store. The sweater costs $30. The store is having a 25% off sale on everything in the store.

EleoNora [17]

30-25%=22.5
30-22.5=7.5

Sara saves $7.50 from the sale. The sale price would be $22.50

7 0

3 years ago

g True or False: Regression analysis is used for prediction, while correlation analysis is used to measure the strength of the a

larisa [96]

Answer:

The given statement is true.

Step-by-step explanation:

Regression Analysis:

Regression analysis is a technique that help us to find or define a relationship between a dependent and an independent variable.
It helps us to predict the dependent variables with the help of independent variables.
Various techniques are used for the prediction of independent variable.
It is a type of predictive statistical technique and helps us to find whether there is a significant relationship between the dependent and the independent variable.

Correlation analysis:

Correlation is a technique that help us to find or define a relationship between two variables.
It is a measure of linear relationship between two quantities.

It is not necessary that the that out of the two variable one needs to be dependent and the other to be independent.
Correlation can be positive, negative or zero correlation.

Thus, the given statement is true.

5 0

3 years ago

Jeremy analyses one of his parachute jumps. He draws a graph showing his velocity up to the opening of his parachute. a) Estimat

jeyben [28]

Answer:

Jeremy's acceleration is about $1\,\frac{m}{s^2}$ at t =10 s

His average speed is about 44.5 m/s in this section of his jump approximating with points on the curve (under-estimate)

His average speed is about 46 m/s if using the tangent line (over estimate)

Step-by-step explanation:

Jeremy's acceleration can be estimated by the curve's derivative at that point. That is the slope of the tangent line to the velocity curve at x = 10 sec. Please see attached image where the tangent line is drawn in orange, and the points to use to calculate its slope are drawn in green.

These points are : (6, 42) and (14,50) which using the slope formula give:

$slope=\frac{y_2-y_1}{x_2-x_1}= \frac{50-42}{14-6}=\frac{8}{8} \frac{m}{s^2} = 1\,\frac{m}{s^2}$

So his acceleration at that point is about $1\,\frac{m}{s^2}$

Now, using about the same interval of x-values (from 6 to 14), the corresponding speeds are approximately: 40 (for time 6 seconds) and 49 (for time 14 seconds (look for the red dots on the attached image). Since the average velocity is given by the integral of the function between those points divided by the length of the interval where it is calculated:

$v_{average}=\frac{area}{interval\,\,length}$

and we don't have the actual velocity function to estimate the integral, we can approximate this area by that of a trapezoid that connects the red dots with the bottom of the horizontal axis (see red trapezoid in the image). Clearly from the image, this approximation would give us an under-estimate of the actual average speed.

The area of this trapezoid is: approximately:

$Trapezoid\,\, area=(49+40)\,8/2=356$

Then the average velocity estimated from it is:

$v_{average}=\frac{356}{8} \frac{m}{s} =44.5\,\frac{m}{s}$

If the area is approximated instead with the trapezoid form by the green points we used to calculate the acceleration (this would give us an over-estimate):

$Trapezoid\,\, area=(50+42)\,8/2=368$