two-fifths of a number is decreased by three.find the value of the expression if the number is twenty five
1 answer:
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Answer:
Step-by-step explanation:
Hello!
Given the variables
X: daily hotel room rate
Y: amount spent on the entertainment
See second attachment for scatter plot.
The population regression equation is E(Yi)= α + βXi
To estimate the y-intercept and the slope of the regression equation you have to apply the following formulas:
a= Y[bar]-bX[bar]
n= 9; ∑X= 945; ∑X²= 103325; ∑Y= 1134 ∑Y²= 148804; ∑XY= 123307
X[bar]= ∑X/n= 945/9= 105
Y[bar]= ∑Y/n= 1134/9= 126
a= 126 - 1.03*105= 17.49
^Y= 17.49 + 1.03Xi
Slope interpretation: The estimated average amount spent on entertainment increases 1.03 every time the daily hotel room rate increases one unit.
If the room rate for Chicago is $128 (X), to predict the mount spent in entertainment (Y) you have replace it in the estimated regression line:
^Y= 17.49 + 1.03Xi= 17.49 + 1.03*128= 149.33
The expected amount spent on entertainment for Chicago is $149.33
I hope this helps!
Answer: option D
Step-by-step explanation:
Remember the cosine identity:
Given the right triangle DFE shown in the image, you can identify that the adjacent side and the hypotenuse for the angle F of this triangle are:
Now you can substitute values into and then reduce the fraction.
THerefore you get: